LDCU_L1M1 PDF - Medicine 1

MODULE 1 - EARLY EMRYOLOGY, ORGANIZATION, GENERAL PLAN OF THE BODY, AND TERMINOLOGY OUTLINE I. Definition of Terms II. Levels of Organization of the Human Body III. Major Organ Systems of the Body A. Organ Systems...

MODULE 1 - EARLY EMRYOLOGY, ORGANIZATION, GENERAL PLAN OF THE BODY, AND TERMINOLOGY OUTLINE I. Definition of Terms II. Levels of Organization of the Human Body III. Major Organ Systems of the Body A. Organ Systems 1. Integumentary System 2. Skeletal System 3. Muscular System 4. Nervous System 5. Endocrine System 6. Cardiovascular System 7. Lymphatic System 8. Respiratory System 9. Digestive System 10. Urinary System 11. Reproductive System IV. Anatomical Position A. Importance environment that it serves to protect and maintain. The V. Common prefixes & suffixes integumentary system includes the epidermis, dermis, VI. Common descriptive terms VII. Areas & quadrants of abdomen hypodermis, associated glands, hair, and nails. VIII. Body Planes IX. Common terms LAYERS OF THE SKIN A. Terms of location, position, direction  Epidermis - The outermost layer of the skin is the B. Terms of movement superficial layer, and it is the thinner layer of the skin. X. Body cavities A. Organs in each body cavity o Stratum corneum (cornified layer) – contains dead, XI. Learning Issues non-nucleated cells filled with keratin filaments. It is the outermost layer of the epidermis and contains flat keratinocytes that produce keratin. DEFINITION OF TERMS o Stratum lucidum (clear layer) – contains translucent  Embryology - A subspecialty of developmental anatomy, cells filled with keratin filaments. It is the second layer considers changes from conception to the end of the eighth of the epidermis only present in the thick skin areas like week of development. soles and feet.  Histology - Examines tissues, which are composed of cells o Stratum granulosum (granular layer) – flattened and the materials surrounding them. layer, waterproof barrier that functions to prevent fluid loss from the body. It is the middle layer of the  Gross Anatomy - The study of structures that can be epidermis. examined without the aid of a microscope, can be o Stratum spinosum (prickle cell layer) – contains approached either systemically or regionally. post-mitotic cells from stratum basale that contain  Physiology - Scientific investigation of the processes or keratin fibrils; melanosomes, Langerhans cells. It is the functions of living things superficial layer of the stratum basale and keratinocytes produce lamellar bodies. LEVELS OF ORGANIZATION OF HUMAN BODY o Stratum basale (basal layer) – contain stem cells that  Chemical Level – Involves how atom such as hydrogen is constantly undergoing mitosis regenerate other and carbon, interact and combine into molecules. layers. It is the deepest layer of the epidermis.  Cell Level - are the basic structural and functional units of all living organisms, it contains smaller structure inside called organelles.  Tissue Level – Group of cells in with the same function and structure. This helps us understand how organs function.  Organ Level - Composed of two or more tissue types that perform one or more common functions  Organ System Level - group of organs that together perform a common function or set of functions and are therefore viewed as a unit.  Organism Level - any living thing considered as a whole— whether composed of one cell, such as a bacterium, or of trillions of cells, such as a human. MAJOR ORGAN SYSTEMS OF THE BODY INTEGUMENTARY SYSTEM  The largest organ of the body that forms a physical barrier between the external environment and the internal MARUHOM 1  TRANS: Module 1 o Hair papilla - vascular connective tissue o Arrector pili - smooth muscle ; connects the undersurface of the follicle to the superficial part of the dermis  Skin glands o Sebaceous glands - secrete an oily substance called sebum. Situated on the sloping undersurface of the follicles and lie within the dermis. Sebum is an oily material that helps preserve the flexibility of the emerging hair. o Sudoriferous (sweat) glands - release sweat into the hair follicles or onto the skin surface through pores. These are long spiral, tubular glands distributed over the surface of the body. It has excretory functions of the body and regulate body temperature o Ceruminous gland - modified sweat gland in the external ear.  Nails - Nails are homologous to the stratum corneum of the epidermis and contain a variety of minerals, such as calcium. They consist of compacted and layered keratin- filled squames (scales). The arrangement and cohesion of the squamosa are responsible for the hardness of nails. A nail consists of the nail plate, nail folds, nail matrix, nail bed and hyponychium.  Dermis - It is the second deepest layer of the skin. o Papillary dermis - It is the first layer of the dermis, and LANGER’S LINES it is composed of areolar connective tissue, and  Langer's lines, Langer lines of skin tension, or sometimes- contains thin collagen and fine elastic fibres. It is more called cleavage lines, are topological lines drawn on a map superficial and significantly thinner layer of the dermis. of the human body. They are parallel to the natural Its main function is to provide superficial dermal and orientation of collagen fibers in the dermis, and generally epidermal layers with sufficient nutrients. perpendicular to the underlying muscle fibers. Langer's o Reticular dermis - It lies under papillary dermis, lines have relevance to forensic science and the composed of dense irregular connective tissue with development of surgical techniques. They are important bundles of thick collagen and some course of elastic when making and closing wounds, ideally all wounds fibres. These fibers support your skin’s overall should be made parallel to Langer's lines to optimize the structure, as well as allow it to move and stretch. cosmetic outcome. These topographical landmarks are used in surgical procedures as guidelines for points of incisions. Incision along these lines result in healing with minimal scarring and subsequently, a less apparent postoperative scar and promotes hypertrophic scarring.  Hypodermis - It is the third deepest layer of the skin, and it is also called the fatty layer of the skin. APPENDAGES OF THE SKIN  Hair or pili - Hairs are filamentous cornified structures, which grow out of the skin and cover most of the body surface. Several areas of the body like the palms, soles, flexor surface of the digits and specific parts of the reproductive organs are devoid of hairs. Hairs are important in sensing, thermoregulation and protection against injury and solar radiation. It grows out of follicles and the follicles lie obliquely to the skin surface. o Hair bulbs - expanded extremities ; penetrate to the deeper part of the dermis MARUHOM 2  TRANS: Module 1 SKELETAL SYSTEM BONE MATRIX  Known as body’s central framework (aka musculoskeletal  The intercellular substance of the bone that forms most of system). It is the body system composed of bones and the mass of the bone. cartilage and performs the following critical functions for the o Organic - makes about half of the weight of the bone. human body: supports the body, facilitates movement, It mostly consists of calcium hydroxyapatite, but there protects internal organs, produces blood cells, and stores are also significant amounts of bicarbonate, citrate, and releases minerals and fat. magnesium, potassium, and sodium ions. o Inorganic - consists of collagen fibers (type I), TYPES OF BONE TISSUE proteoglycans, and glycoproteins (e.g., osteonectin  Compact (cortical bone) - The hard/dense outer tissue of and osteocalcin). the bones, which consists of closely, packed osteons or haversian systems. BONE CELLS  Spongy (cancellous) bone – lighter and less dense than  Osteocyte – a cell that lies within the substance of fully compact bone. Spongy bone consists of plates (trabeculae) formed bone. Mature bone cells with dendritic processes and bars of bone adjacent to small, irregular cavities that that extend through canaliculi in the calcified matrix. Its contain red bone marrow. Function: increase bone strength function is the maintenance of the bone matrix and a without greatly increasing the bone’s weight. sensitive detector of stress.  Osteoblast – primarily responsible for synthesizing bone matrix protein and minerals during early bone formation in the embryo. It lines the bony spicules and secrete organic components of bone matrix (also known as osteoid). Osteoids are composed of collagen type 1 and some collagen type 5, proteoglycan, and glycoproteins. It separates the osteoblast layer and the pre-existing bone surface. Inactive osteoblasts become flattened and are known as the bone lining cells.  Osteogenic – plays a prodigal role in bone repair and growth.  Osteoclast – cells that degrade bone to initiate normal bone remodeling and mediate bone loss. These are large, motile, multinucleated cells. Its size is due to the fusion of bone marrow-derived monocytes (origin). THE HAVERSIAN SYSTEM  Made of osteons of compact bone  Microscopic tubes or tunnels in cortical bone that house nerve fibers and a few capillaries. Haversian canals are formed by lamellae (a sheetlike membrane found within a chloroplast of an autotropic cell.), or concentric layers of bone, and are contained inside osteons. Haversian canals and osteons are part of the Haversian system, which allows nutrients to pass between the blood and bone. This allows bone to get oxygen and nutrition without being vascular. These canals also communicate with bone cells using special connections, or canaliculi. (Facilitates the deposit and storage of mineral salts, which essentially gives bones their strength.) o Haversian Canals - surround the blood vessels and nerve fibers o Perforating Canals - deliver blood to the central canals o Lamellae - Extracellular matrix around that gives rigidity and hardness to compact bones BONES ACCORDING TO SHAPE  Long bones - are hard, dense bones that provides strength structure & mobility (shaft & two ends). Most of the bones of the upper and lower limbs are long bones. (e.g., the humerus, femur, metacarpals, metatarsals, and phalanges)  Short bones - are shaped roughly as a cube & contain mostly of spongy bone. Usually found in the hand and foot (e.g., the scaphoid, lunate, talus, and calcaneum)  Flat bone - made up of a layer of compact bone found in the vault of the skull (e.g., the frontal and parietal bones). It protects vital organs.  Irregular bone - vary in shape and structure, therefore does not fit to the other categories (protects internal organs like the spinal cord. These are bones not assigned to the previous groups(e.g., the bones of the skull, the vertebrae, and the pelvic bones). MARUHOM 3  TRANS: Module 1  Sesamoid bone - small bone commonly found embedded  The cartilage model continues to grow serving as within a muscle/tendon near joint surface. The patella is the a structural scaffold for the bone development and largest sesamoid bone. is eventually restored and replaced by the bone.  Bone remodeling - removal of existing bone by osteoclast STRUCTURES OF LONG BONES and deposition of new bone by osteoblast.  Epiphyses - the bulbous ends of long bones composed of o Surface remodeling - bone deposition under certain cancellous bone covered by a thin layer of compact cortical region of periosteum (e.g. bone of of the skull is being bone. It is the site of lengthwise bone growth. reshaped to accomodate the growing brain) o Internal remodeling - continues change because  Diaphysis - the cylindrical part of long bones. It is almost bone must be reserved from one area and added to very dense/compact bone with a thin region of cancellous another in order to meet changing stress (e.g Weight bone on the inner surface around the central marrow cavity. change, alteration, or micro fracture of bones)  Medullary cavity - space within the diaphysis  Red marrow - site of blood cell production, and yellow CATEGORIES OF SKELETON marrow consist of fat  Periosteum - covers the outer surface of bone. The outer  Axial skeleton - forms the central axis of the body. It layer containing vessels and nerves consists of the skull, auditory ossicles, hyoid bone, vertebral  Endosteum – lines cavities inside bone and contains column, and thoracic cage. osteoblast and osteoclast  Appendicular skeleton - allows movement of our appendages and support our weight in an upright position. It consists of the bones of the upper and lower limbs and their girdles. CRANIAL BONES  Frontal (flat bone) – resembles a cockleshell in form. It consists of two portions vertical or frontal, situated at the anterior part of the cranium, forming the forehead. It has a horizontal or orbito-nasal portion, which enters into the formation of the roof of the orbits and nose.  Parietal (flat bone) – located on the sides of the head; has an irregular quadrilateral form  Temporal (irregular) – situated at the base of the skull, under parietal  Occipital (flat) – found at the back of the skull. It is trapezoid in form, curved upon itself  Sphenoid (irregular) – situated at the anterior part of the OSSIFICATION & BONE REMODELING base of the skull, articulating with all the other cranial bones,  Ossification – The formation of new bone by osteoblasts. which binds it firmly and solidly together. It will occur multiple times during life as a fetus, when  Ethmoid (irregular) – an exceedingly light spongy bone, of growing larger, and any time in life when a fracture is a cubical form, situated at the anterior part of the base of repaired. Ossification occurs by appositional growth on the the cranium, between two orbits, at the root of the nose. surface of previously existing material, either bone or cartilage.  Paired - parietal & temporal o Intramembranous ossification – starts in embryonic development. Osteoblasts differentiate directly from CRANIAL FOSSAE progenitor cells in condensed membranes of mesenchyme to secrete osteoid. Mostly occurs in flat  Anterior cranial fossa – house the frontal lobes of the bones. brain and the most shallow part. o Endochondral ossification - requires the presence of  Middle cranial fossa - “butterfly” shaped, it accommodates cartilage template. Most of the long and short bones of the pituitary gland and temporal lobes. It encompasses the the body develops in two steps: area from the posterior portion of the lesser wings of the  Miniature hyaline cartilage model is formed in sphenoid bone to the petrous part of the temporal bone. the region of the developing embryo where bone  Posterior cranial fossa - bordered anteriorly by the is to be developed. posterior portion of the petrous part of the temporal bone, posteriorly by the occipital bone, and laterally by the parietal MARUHOM 4  TRANS: Module 1 bone. The cerebellum and a portion of the brainstem are located in this fossa FACIAL BONES  Maxilla (2) - pair of bones that forms the dominant poetion of the face  Mandible - largest bone in the human skull  Conchae (2) - long, narrow bone that protrudes into the breathing passage of the nose.  Nasal (2) - upper part of the nose CRANIAL FONTANELS  Vomer - midline bone that occupies & divides the nasal cavity  Allow for the growth of the brain and skull  Lacrimal (2) - located medial wall of the orbit  Allow flexibility in the skull during the birth process, as well  Zygomatic (2) - cheekbone/malar bone as growth of the head after birth. The spaces between the  Palatine (2) - located inside, paired bones between the bones that remain open in babies/young children are called maxillae & the pterygoid process of the sphenoid bone. “soft spots”  Anterior (top of the middle head/forward center) – the junction where the two frontal and two parietal bones meet. The anterior fontanelle remains soft until about 18 months to 2 years of age.  Posterior (back of the middle of the head) – the junction of the two parietal bones and the occipital bone. The posterior fontanelle usually closes first, before the anterior fontanelle, during the first several months of an infant’s life (within 2 months of birth) CRANIAL SUTURES  Fibrous bands of the tissue that connects the bone and skull  Allows the bones to move during the birth process (act like an expansion joint)  Allows the bone to enlarge evenly as the brain grows and the skull expands  Metopic - This extends from the top of the head down the middle of the forehead, toward the nose. The 2 frontal bone PARANASAL SINUSES plates meet at the metopic suture.  The sinuses found in the frontal bone, the ethmoid bone,  Coronal – This extends from ear to ear. Each frontal bone the sphenoid bone, and the maxilla are called the paranasal plate meets with a parietal bone plate at the coronal suture. sinuses. The sinuses have two major functions:  Sagittal – This extends from the front of the head to the o they decrease the weight of the skull back, down the middle of the top of the head. The 2 parietal o they act as a resonating chamber when speaking bone plates meet at the sagittal suture.  Lambdoid – This extends across the back of the head. Each parietal bone plate meets the occipital bone plate at the lambdoid suture. MARUHOM 5  TRANS: Module 1 VERTEBRAL COLUMN  Major Functions: o Supports the weight of the head and trunk o Protects the spinal cord o Allows spinal nerves to exit the spinal cord o Provides a site for muscle attachment o Permits the movement of the head and trunk  33 vertebrae  Cervical vertebrae (7) – located in the vertebral column region with the greatest range of motion. It supports and moves the head.  Thoracic vertebrae (12) – least movable of the five regions MIDDLE EAR BONES due to the articulation of the thoracic vertebrae with the ribs. Supports the thoracic cage, which houses and protects the  Hammer (Malleus) - attached to the eardrum heart and lungs  Anvil (Incus) – middle of the chain of bones  Lumbar vertebrae (5) – supports the majority of body  Stapes – attached to the membrane covered opening that weight. Massive bodies, and heavy, rectangular transverse connects the middle ear with the inner ear. and spinous processes.  Sacrum (5 fused) – located between the two hip bones. It articulates with each hip bone by way of the auricular surfaces, forming the sacroiliac joint  Coccyx (3-4 fused) – commonly referred to as the tailbone. The terminal portion of the vertebral column. Formed from three to five semifused vertebrae. In males, the coccyx may project anteriorly, but in females, it often projects more inferiorly.  Invertebral disc – lies between adjacent vertebrae in the vertebral column. HYOID BONE  U-shaped bone situated at the root of the tongue in the front of the neck and between the lower jaw and the largest cartilage of the larynx, or voice box. The primary function of the hyoid bone is to serve as an attachment structure for the tongue and for muscles in the floor of the oral cavity.  In the cervical spine, a normal range of lordosis is 20 to 40 degrees, and in the lumbar section, a normal lordotic spine curve would fall between 40 and 60 degrees; at the thoracic level, a normal range of kyphosis is between 20 and 40 degrees. MARUHOM 6  TRANS: Module 1 BONES OF THE THORAX  Sacrum - wedged-shaped sacrum is usually composed of  Thoracic vertebrae (12) - Twelve thoracic vertebrae are five fused sacral vertebrae in adults; is located between the strong bones located in the middle of the vertebral column, hip bone sandwiched between the cervical vertebrae and lumbar  Coccyx (tailbone) - is a small triangular bone that is usually vertebrae. formed by fusion of the four rudimentary coccygeal  Ribs – there are twelve pairs of ribs: classified as true ribs vertebrae. It does not participate in support of the body and false ribs. Ribs 1-7 are true ribs since they attach weight when standing; however, when sitting, it may flex directly through the costal cartilage to the sternum. Ribs 8- anteriorly indicating that it is receiving some weight. 12 are false ribs since they do not attach directly to the sternum.  Sternum – the sternum or breastbone is described as sword shaped and has three parts. The manubrium “sword handle” , the body, or gladiolus, is the “blade” , and xiphoid process is the “sword tip” PECTORAL GIRLDE BONES  Consists of two bones that make up the shoulder  Scapula - COLLARBONE  Clavicle - SHOULDER BLADE BONES OF THE UPPER EXTREMITY  Humerus (arm bone) - the largest bone in the upper limb. BONES OF THE LOWER EXTREMITY It serves as the attachment of 13 muscles that contributes  Femur - is the longest and heaviest bone in the body; to movements of the hand and elbow Single bone of the thigh  Ulna - the stabilizing bone of the forearm; long bone in the  Patella (knee cap) - is a large sesamoid bone that is forearm medially and parallel to the radius formed in the tendon of the quadriceps femoris muscle after  Radius - the lateral and shorter of the two forearm bones; birth; articulates with the patellar surface of the femur. lies laterally and parallel to ulna  Tibia (shin bone) - articulates with the condyles of the  Carpals – make up the bones of the wrist; eight carpal femur superiorly and the talus inferiorly and in so doing bones transmits the body’s weight; is the second largest bone in  Metacarpals – bones of the hand; five metacarpals each the body one is related to a digit.  Fibula - no function in weight bearing, mainly function as a  Phalanges - bones of the fingers muscle attachment, providing distal attachment (insertion) for one muscle and proximal attachment (origin) for eight muscles; important for the stability of the ankle joint.  Tarsals - consists of seven bones: talus, calcaneus, cuboid, navicular, and three cuneiforms; most of its surface is covered with articular cartilage.  Metatarsals - five metatarsals; the 1st metatarsal is shorter and stouter than the others, while the 2nd metatarsal is the longest.  Phalanges - 14 of the lower limb are as follows: the 1st digit (great toe) has 2 phalanges (proximal and distal); the other four digits have 3 phalanges each: proximal, middle, and distal PELVIC GIRDLE BONES  Hip bone - is the large, flat pelvic bone formed by the fusion of three primary bones: ilium, ischium, and pubis MARUHOM 7  TRANS: Module 1  Foot arches - help in proportional body weight distribution  Fibrous joints – consist of bones united by fibrous to weight-bearing area. connective tissue. They allow little or no movement. o Medial longitudinal arch  Cartilaginous joints – consist of bones united by cartilage, o Lateral longitudinal arch and they exhibit slight movement o Anterior transverse arch  Synovial joints – capable of considerable movement; the space around the articular surfaces of the bones in a synovial joint is called the joint cavity, which is filled with synovial fluid and surrounded by a joint capsule. Synovial joints are classified according to the shape of the adjoining articular surfaces. There are six types of synovial joints: o Hinge – resemble the hinge on a door, so that flexion and extension movements are possible (e.g. elbow, knee, and ankle joints) o Pivot – central bony pivot is surrounded by a bony ligamentous ring, and rotation is the only movement possible (e.g. atlantoaxial and superior radioulnar joints) o Saddle – the articular surfaces are reciprocally concavoconvex and resemble a saddle on a horse’s back. These joints permit flexion, extension, abduction, adduction, and rotation (e.g. carpometacarapal joint of the thumb) JOINTS o Condyloid – have two distinct convex surfaces  A joint is the part of the body where two or more bones meet that articulate with two concave surfaces. The to allow movement. Every bone in the body – except for the movements of flexion, extension, abduction, and hyoid bone in the throat – meets up with at least one other adduction are possible together with a small bone at a joint. The shape of a joint depends on its function. amount of rotation. (e.g. metacarpophalangeal A joint is also known as an articulation joints or knuckle joints) Functional category: o Ball and socket – ball shaped head of one bone  Synarthroses – non movable joints fits into a socketlike concavity of another. This arrangement permits free movements, including  Amphiarthroses – slightly movable joints flexion, extension, abduction, adduction, medial  Diarthroses – freely movable joints rotation, lateral rotation, and circumduction. (e.g. shoulder and hip joints) o Plane – the opposed articular surfaces are flat or almost flat, and this permits the bones to slide on one another (e.g. sternoclavicular and acromioclavicular joints) Structural category: MARUHOM 8  TRANS: Module 1 Structures that stabilize a joint:  Ligaments – bone to bone  Tendons – muscle to bone  Ligament - a fibrous connective tissue that attaches bone CARTILAGE to bone, and usually serves to hold structures together and  Cartilage is a strong, flexible connective tissue that protects keep them stable. your joints and bones. It acts as a shock absorber  Bursa - a small, fluid-filled sac within your body that lies throughout your body. Cartilage at the end of your bones near bony prominences and joints. The bursa acts as a reduces friction and prevents them from rubbing together cushion between muscles, ligaments, and bones and when you use your joints. allows structures to glide and slide past one another with Types of cartilage ease and with minimal friction.  Hyaline – flexible and resilient; chondrocytes appear spherical and held by lacuna; collagen is the only fiber found in matrix  Fiber – resists compression and tension; rows of thick collagen fibers alternating with rows of chondrocytes in matrix  Elastic – highly bendable; matrix with elastic as well as collagen fibers MUSCULAR SYSTEM Types of muscle tissue:  Skeletal muscle - voluntary muscle (can be involuntary- reflexes) and constitutes about 40% of the body’s weight.  Smooth muscle - voluntary muscle and constitutes about 40% of the body’s weight.  Cardiac muscle - also involuntary muscle and is found only in the heart. MARUHOM 9  TRANS: Module 1 groups (i.e. intermuscular septa, investing fascia, subserous fascia, retinacula) to perform specific functions (e.g. retinacula – hold tendons in place during joint movements)  Tendon – mostly tough collagen fibers. It anchors muscles, providing durability and conserving space  Aponeurosis – sheet of fibrous connective tissue, or an expanded tendon. It is in the origin or insertion of flat muscle. NAMING SKELETAL MUSCLES  Direction of the muscle fibers – muscle name includes rectus (meaning: straight), fibers run parallel to the imaginary line (e.g. rectus femoris: straight muscle of the thigh)  Relative size of the muscle – maximus (larges), minimus (smallest), and longus (long) (e.g. gluteus maximus – largest muscle of the gluteus group)  Location of the muscle – named for the bone with which they are associated (e.g. temporalis and frontalis muscle overlie skull temporal and frontal bones) STRUCTURES OF SKELETAL MUSCLE  Number of origins – e.g. biceps – two origins, triceps – three origins, and so  Location of the muscle’s origin and insertion – named for their attachment sites (e.g. sternocleidomastoid muscle has its origin on the sternum and clavicle and inserts on the mastoid process of the temporal bone)  Shape of the muscle – e.g. deltoid muscle is roughly triangular (deltoid means “triangular”)  Action of the muscle – flexor, extensor, adductor appear in their names (e.g. adductor muscles of the thigh all bring about its adduction) NERVOUS SYSTEM Consists of two major divisions: the central nervous system and the peripheral nervous system. These two systems communicate with each other and with the body to maintain homeostasis.  Homeostasis – the maintenance of nearly constant conditions in the internal environment  Skeletal muscle fibers – are very unique cells, they develop from the fusion of several hundred embryonic cells called myoblasts. The result of skeletal muscle fiber formation is an enormous cell with several hundred nuclei just under the plasma membrane.  Connective tissue – holds the tissues together and provides a supporting framework for the body o Endomysium – delicate network of connective tissue that surrounds muscle fibers and forms their immediate external environment. It is the site of metabolic exchange between muscle and blood, and contains capillaries and bundles of small nerve fibers. CENTRAL NERVOUS SYSTEM o Perimysium – loose connective tissue which subdivides each whole muscle into numerous  Receives information from and sends information to the fascicles. It serves as passageway for blood vessels body and nerves that supply each fascicle.  Can be thought of as the key decision maker o Epimysium – outer fibrous connective tissue layer  Consists of the brain and spinal cord surrounding all muscles. It separates the muscles from  Spinal cord – housed within the vertebral canal of the nearby structures. vertebral column  Fascicle – bundle of muscle fibers. It is divided into two  Brain – housed within the skull zones: o Superficial – composed of loose tissue, located Divisions of the brain: directly under the dermis. It contributes to the mobility  Forebrain - cerebrum, diencephalon, telencephalon of the skin, acts as insulator  Midbrain o Deep – composed of compacted and regularly  Hindbrain - medulla oblongata, pons, cerebellum arranged collagenous fibers. It divides muscles into MARUHOM 10  TRANS: Module 1  Diencephalon coordinated skeletal muscle movements; responsible for o Thalamus – relays sensory impulses to cerebral proper balance and posture cortex; relays impulses between cerebral motor cortex and lower motor centers; involved in memory o Hypothalamus – chief integration center of autonomic (involuntary) nervous system; regulates body temperature, food intake, water balance and thirst; regulates hormonal output of anterior pituitary gland and acts as an endocrine organ (producing ADH and oxytocin)  Cerebrum - divided into left and right hemispheres by a longitudinal fissure. It has four lobes: frontal, parietal, temporal and occipital. The cortex of the cerebrum contains: ridges (gyri) and grooves (sulci or fissures). Gyri are numerous folds on each hemisphere that greatly increase the surface area of the cortex. Meanwhile the sulcus are grooves between the gyri, it divides each hemisphere into lobes o Frontal lobe - smell, motor control, emotion and language; contains the motor cortex, prefrontal cortex and Broca’s area; the anterior region (prefrontal cortex) is involved in higher level cognitive functioning; the Broca’s area is essential for language production o Parietal lobe - sensory center of the brain as it contains the somatosensory cortex; major center for receiving and evaluating most sensory information except for smell, hearing taste, and vision o Temporal lobe - hearing, memory and emotion; auditory cortex and Wernicke’s area can be located in  Midbrain – contains visual and auditory reflex centers; this lobe contains subcortical motor centers; contains nuclei for o Occipital lobe - receiving and integrating visual cranial nerves III and IV input; contain the visual cortex PERIPHERAL NERVOUS SYSTEM  Responsible for detecting stimuli in and around the body Major Sulci: and sending that information to the CNS and then  Central or Rolando Sulcus - separates the frontal lobe communicating messages from the CNS to the body from the parietal lobe  The messenger that provides input about the body to the  Lateral or Sylvian fissure - divides temporal lobe from CNS and then delivers the CNS decision on how to respond frontal and parietal lobe to a particular set of stimuli  Longitudinal fissure - divides the cerebral hemisphere  Consist of all the nervous tissue outside the CNS which into left and right includes the nerves, ganglia, and sensory receptors to the  Parieto Occipital fissure - separates parietal lobe from the CNS occipital lobe Two primary receptors:  Calcarine sulcus - sulcus surrounded by the visual  Sensory division - Afferent division (afferent = “toward”); receptive area; divides the cuneus from the lingual gyrus transmits electrical signals from specialized receptors in the body towards the CNS  Pons – relays information from the cerebrum to the o Somatic sensory division - carries signals from skin, cerebellum; cooperates with the medullary centers to muscles, joints and bones control respiratory rate and depth; contains nuclei of cranial o Visceral sensory division - carries signals from nerves V-VII viscera of thoracic and abdominal cavities  Medulla oblongata – relays ascending sensory pathway  Motor Division - Efferent division (efferent = ”away”) impulses from skin and proprioceptors; contains nuclei o Somatic nervous – Associated with voluntary control controlling heart rate, blood vessel diameter, respiratory movements via skeletal muscles; involved in reflex rate, vomiting, etc.; relays sensory information to the actions cerebellum; contains nuclei of cranial nerves VIII-XII o Autonomic nervous system - maintains homeostasis  Cerebellum – processes information from cerebral motor of the body by regulating many involuntary activities cortex, proprioceptors, and visual and equilibrium including heart rate, breathing rate, body temperature, pathways; provides “instructions” to cerebral motor cortex digestive processes, and urinary functions and subcortical motor centers, resulting in smooth MARUHOM 11  TRANS: Module 1  Sympathetic NS – fight or flight; readies the body for physical activities  Parasympathetic NS – rest and digest; regulates resting functions such as digesting food or slowing the heart rate CRANIAL NERVES  Olfactory nerve (I) - smell  Optic nerve (II) - vision  Oculomotor nerve (III) -innervates 4 of the 6 extrinsic eye muscles and the upper eyelid (superior, inferior, medial rectus muscles and the inferior oblique muscle)  Trochlear nerve (IV) - innervates 1 of the 6 eye muscles responsible for moving the eyeball (superior oblique) SPINAL NERVES  Trigeminal nerve (V) - chief sensory nerves for the face 31 spinal nerves: and head, receiving impulses of pain, temperature, and C - Cervical nerve (C1-C8) touch; the motor fibers stimulate the muscles of T- Thoracic nerve (T1-T12) mastication; 3 main branches: Ophthalmic, Maxillary and L - Lumbar nerve (L1-L5) Mandibular; they are the chief sensory nerves for the face S - Sacral nerve (S1-S5) and head, receiving impulses of pain, temperature, and Co- Coccygeal nerve touch; the motor fibers stimulate the muscles of mastication  Abducens Nerve (VI) - supply the lateral rectus muscle of Cervical the eyeballs causing abduction  located at the top of the spine and of the cervical vertebrae  Facial Nerve (VII) - the motor fibres supply the muscles of  C1, C2, and C3 = head and neck including forward, facial expression; the sensory fibres convey impulses from backward, and sideward movements the taste buds in the anterior 2/3 of the tongue to the taste  C4 = upper shoulder movements, as well as helping to perception area in the cerebral cortex power the diaphragm.  Vestibulocochlear nerve (VIII) - Involved in senses of  C5 = deltoids and biceps, the areas of the upper arm, down hearing and balance to the elbows  Glossopharyngeal nerve (IX) - involved in taste and  C6 = wrist extensions with some supply given to the biceps supplies tactile sensory innervation from the posterior  C7 = triceps as well as the wrist extensor muscles tongue, middle ear, and pharynx; sensory for receptors that  C8 = hands as well as finger flexion (hand grip) monitor blood pressure and gas levels in the blood; parasympathetic to the parotid salivary glands; it is somatic Thoracic motor to one muscle of the pharynx and supplies  located at the thoracic vertebrae of the spine parasympathetic innervation to the parotid salivary glands;  T1 and T2 = top of the chest, arms and hands it is essential for the swallowing and gag reflexes  T3, T4, and T5 = chest wall as well as aid in breathing  Vagus Nerve (X) - involved in the sense of taste, monitor  T6, T7, and T8 = chest and down into the abdomen blood pressure and gas levels in the blood; conveys  T9, T10, T11, T12 = abdomen and lower in the back sensory information from the thoracic and abdominal organs; the parasympathetic part of the vagus nerve is very Lumbar important in regulating the functions of the thoracic and  L1 = groin as well as the genitals abdominal organs.  L2, L3, and L4 = thighs and the inner side of the lower legs.  Accessory nerve (XI) - a somatic motor nerve that has They also help to control movements of the hip and knee both cranial and spinal roots; It supplies the muscles sternocleidomastoid and trapezius muscle  L5 = outer side of the lower legs and the upper foot. These  Hypoglossal nerve (XII) - a somatic motor nerve that also helps to control the hips, knees, feet, and to arises from the ventral surface of the medulla oblongata; It movements. supplies the intrinsic tongue muscles, three of the four extrinsic tongue muscles, and two throat muscles Saccral (thyrohyoid and geniohyoid)  S1 = hips and the groin area  S2 = back of the thighs  S3 = medial buttock area  S4 and S5 = perineal area Coccygeal  CO1 = skin MARUHOM 12  TRANS: Module 1 ENDOCRINE SYSTEM PINEAL GLAND  also called “ Pineal body or epiphysis cerebri”  located beneath the back part of the corpus callosum  secretes the hormone : Melatonin  help control the circadian cycle of sleep and wakefulness  shaped like a “tiny pinecone” PITUITARY GLAND  Small pea-sized endocrine gland  Located at the base of your brain below your hypothalamus  Also known as “hypophysis”  Divided into two main sections: the anterior and posterior pituitary  Anterior pituitary makes and releases the following hormones: ACTH, FSH, growth hormone, luteinizing hormone, prolactin, thyroid-stimulating hormone MENINGES  Posterior pituitary: Antidiuretic hormone  Meninges are connective tissue membranes that surround (vasopressin), oxytocin the spinal cord and brain Meningeal layers:  Dura mater - the most superficial and thickest membrane (composed of dense irregular connective tissue); lines inner surface of skull by its fusion with periosteum; separated from the arachnoid by potential subdural space  Arachnoid mater - delicate thin cobweb like membrane; attaches to pia mater by trabeculae; subarachnoid space is filled with CSF  Pia Mater - soft thin membrane; lines brain and spinal cord extending into all fissures and sulci; extends around blood vessels throughout brain PANCREAS  Main function: maintain healthy blood sugar levels and help Meningeal spaces: with digestion  Epidural space - between the bone and dura mater  Both an organ and gland  Subdural space - between the dura mater and arachnoid  Large gland that lies alongside the stomach mater  Performs two main functions: Exocrine & Endocrine  Subarachnoid space - between the arachnoid mater and  Hormones: Insulin , Glucagon, somatostatin & pia mater pancreatic polypeptide  Cells: Beta cells & Alpha cells  Interspersed with the exocrine cells are clusters of endocrine cells called pancreatic islets or the islets of Langerhans MARUHOM 13  TRANS: Module 1 OVARIES PARATHYROID GLAND  Small , oval-shaped glands  small glands in the neck located behind the thyroid gland  Located on either side of the uterus  Main Hormone: Parathyroid hormone  Hormones: Estrogen, Progesterone  Main Function: Regulate calcium levels in the blood  Estrogen promotes the development of female characteristics and also contributes to the development of reproductive system  After ovulation, the corpus luteum secretes progesterone. Progesterone in combination with estrogen helps maintain the uterine lining during pregnancy HYPOTHALAMUS  acts as your body’s smart control coordinating center TESTES  main function: is to keep your body in a stable state called  two oval-shaped male reproductive glands homeostasis  Lie behind the penis in a pouch of skin called Scrotum  Makes some hormones itself that are stored elsewhere (in  Main Function: to produce sperm & produce hormones your posterior pituitary)  Main Hormone: Testosterone  Secretes hormones that stimulate or suppress the release of hormones in the pituitary gland, in addition to controlling water balance, sleep, temperature, appetite and blood pressure THYROID GLAND  located at the front of the neck just below the larynx  butterfly-shaped  Main function: Regulate the body’s metabolic rate, growth and development  Main hormones: thyroxine (T4), triiodothyronine(T3) ADRENAL GLAND  located on top of your kidneys  adrenal medulla – consists of modified neurons and functions as part of the sympathetic nervous system  adrenal cortex – glandular tissue and secrets steroid hormones called corticosteroids  Main Hormones: Cortisol, Aldosterone & Adrenaline  Main Function: Regulate several bodily functions including metabolism, blood pressure and body’s response to stress MARUHOM 14  TRANS: Module 1  Ventricle pump arterial blood out of the heart (high pressure chambers)  The heart has two functional circuits, the right heart (right atrium and right venticle) is the pulmonary circuit pump.  The left heart (left atrium and left ventricle) is the systemic circuit pump.  The heart is aligned obliquely within the thorax, with an apex directed downward, forward, and to the left.  Left ventricle forms the apex of the heart. Lies at the level of the fifth left intercostal space from the midline.  Heart wall composed of the three layers of tissue: Epicardium (superficial layer), Myocardium (thick, middle layer of the heart), Endocardium (lines the inner surface and forms the internal layer of the heart)  Heart Valves: Tricuspid valve, mitral valve, pulmonary valve and aortic valve.  Internal Septum separates the right and left atrium THYMUS  Interventricular Septum separates the right and left ventricles.  Small gland part of the lymphatic system  The series of changes that take place within it as it fills with  Main Hormones: Thymopoietin, Thymosin and thymulin blood and empties is referred to as the cardiac cycle & thymic humoral factor  Heart consists of two muscular pumps act in series, dividing into two components: the pulmonary and systemic circulation.  Systemic circulation – transports O2 blood to the tissues and brings CO2 blood back to the right side of the heart  Pulmonary circulation – transports CO2 to lungs and brings fresh O2 to the left side of the heart  Right ventricle propels low-oxygen blood  Left ventricle propels the oxygen-rich blood MEDIASTINUM  The heart lies obliquely in the mediastinum, with its base directed posteriorly and slightly superiorly and its apex directed anteriorly and slightly inferiorly  Divided into two areas: Super mediastinum & inferior mediastinum  Anterior mediastinum – immediately at the back of the body of the sternum CARDIOVASCULAR SYSTEM  Middle mediastinum – posterior portion of the anterior HEART mediastinum, you will find the heart here  Posterior mediastinum – posterior of the middle  Shaped like a blunt cone mediastinum, in front of the thoracic verterbra  Located in the mediastinum  Apex – blunt, rounded point of the heart  Base – larger, flat part at the opposite end of the heart  four chambers (two atria and two ventricles)  Atria receive venous blood (low pressure chambers) MARUHOM 15  TRANS: Module 1 HEART WALL Epicardium  Visceral pericardium  Superficial layer of the heart  The serous pericardium is called the epicardium when considered a part of the heart and the visceral pericardium when considered a part of the pericardium Myocardium  Thick, middle layer of the heart  Composed of cardiac muscle cells  Responsible for the heart’s ability to contract Endocardium  Simple squamous epithelium over a layer of connective tissue  Allows blood to move easily through the heart  Covers the surfaces of the heart valves PERICARDIUM  Double-layered, closed sac that surrounds the heart and anchor it within the mediastinum  2 layers: Fibrous and serous  Fibrous – tough; fibrous connective tissue outer layer; fuses with other coats of the great blood vessels passing through it- namely, aorta, pulmonary trunk, superior and inferior vena cava, pulmonary veins  Serous – inner layer of flat epithelial cells, with a thin layer of connective tissue o Parietal pericardium – outer layer of the serous membrane, lines the fibrous coat o Visceral pericardium – inner layer of the serous membrane, at the walls of the heart  Pericardial activity – located betwee the visceral and HEART VALVES parietal pericardia, is filled with a thin layer of pericardial  Atrioventricular valves - to prevent backflow of blood fluid; produced by the serous pericardium, the pericardial  Tricuspid valve – AV valve between the right atrium and fluid helps reduce friction as the heart moves within the right ventricle has 3 cusps pericardium  Bicuspid valve (mitral valve) – AV valve between left atrium and left ventricle has 2 cusps  Pulmonary valve - located between the right ventricle and the pulmonary artery.  Aortic valve - located between the left ventricle and the aorta. MARUHOM 16  TRANS: Module 1 SEPTA  Structures that separate the chambers  Interatrial septum – separates the right and left atrium  Interventricular septum – separates the right and left ventricles LYMPHATIC SYSTEM CHAMBERS OF THE HEART  A group of organs, vessels and tissues that protect you from infection and keep a healthy balance of fluids throughout  Right atrium – receives venous CO2 blood from: your body. o Superior vena cava – venous blood from head, neck,  Originates in the tissue spaces of the body serving as an and upper portion of shoulders; opens into the upper accessory system for the flow of fluid from the tissue spaces part of the right atrium, it has no valve. It returns the into the circulation blood to the heart from the upper half of the body  Maintains fluid balance in tissues, absorps lipids from small o Inferior vena cava – venous blood from the rest of the intestine, and defends against microorganisms and foreign body; opens into the lower part of the atrium; it is substances guarded by a rudimentary, non-functioning valve. It returns the blood to the heart from lower half of the LYMPH body o Coronary sinus – drains most of the blood from the  clear to white fluid made of white blood cells, especially heart wall lymphocytes, the cells that attack bacteria in the blood  Right ventricle – blood flows from RV into the pulmonary  collection of the extra fluid that drains from cells and tissues trunk (that is not reabsrobed into the capillaries)  Left atrium – receives blood from lungs; quadrilateral in  fluid that flows throughout the lymphatic system shape and its anterior shows the openings of the four pulmonary veins from the lungs LYMPHATIC VESSELS  Left ventricle – blood flows from LV into the aorta; wall of  carry lymph away from tissues left ventricle is much thicker than right ventricle; allows for  the thoracic duct is the largest lymphatic vessel stronger contractions to pump blood through systemic  it has valves that ensure a one-way flow of lymph circulation  contraction of lymphatic vessel smooth muscle, contraction of skeletal muscle, and thoracic pressure changes move BLOOD VESSELS the lymph  Arteries – carry blood away from the heart. Classified as: o Elastic arteries – thin-walled with large diameters o Muscular arteries – thick-walled with small diameters o Arterioles – smalles arteries  Capillaries – thinnest of all blood vessels; blood flows from arterioles into capillaries, can do the function of filtration and absorption. Classified as: o Continuous – walls of continuous capillaries have no gaps between the endothelial cells o Fenestrated – have pores called fenestrae that extend completely through the cell o Sinusoidal – large diameter capillaries with large fenestrae  Veins – from capillaries, blood flows into veins, vessels that carry blood toward the heart  Venules – composed of endothelium surrounded by a few smooth muscle cells  Small veins – venules covered with a layer of smooth muscle  Medium or large veins – contains less smooth muscle and fewer elastic fibers than arteries of same size MARUHOM 17  TRANS: Module 1 LYMPH NODES THYMUS  small, round or bean-shaped structures ranging from 1mm  site for maturation of T cells to 25mm long  bilobed gland located in the superior mediastinum, the  Lymphatic tissue in the lymph node is organized into the partition dividing the thoracic cavity into the left and right cortex and the medulla. Lymphatic sinuses extend through parts the lymphatic tissue  increases in size until the first year of life, after which it  Substances in lymph are removed by phagocytosis, or they remains approximately the same size until 60yrs of age, stimulate lymphocytes (or both) when it decreases in size  Lymphocytes leave the lymph nodes and circulate to other tissues MAIN LYMPHATIC BASINS  Contains immune cell to attack foreign substances  Cervical lymph nodes - these nodes located in the neck  An important function of lymph nodes is to filter the lymph, and are responsible for draining lymph from the head and removing bacteria and other materials. In addition, neck regions lymphocytes congregate and proliferate with lymph nodes  Axillary lymph nodes - found in the armpits these nodes as well as carry out their protective functions. drain lymph from the upper limbs,chest and breast  Inguinal lymph nodes - located in the groin area these nodes collect lymph from the lower limbs and genital region RESPIRATORY SYSTEM UPPER RESPIRATORY SYSTEM  Nose - The only external visible part of the respiratory system.  Nasal Cavity - located inside the nose. It is lined with mucous membrane that keeps our nose moist by making mucus  Pharynx - “throat”. It is part of both respiratory and digestive system. It serves a common passageway of food and air.  Larynx - “ voicebox”. It is a hollow tube that lets the air pass through the throat to the trachea.It also contains vocal cords and is essential to human speech. SPLEEN LOWER RESPIRATORY SYSTEM  Largest lymphatic organ located on your left side under your  Trachea -”wind pipe”. It is a long U-shaped tube that ribs and above your stomach connects the larynx to your lungs.  Graveyard of worn-out RBCs (loses its flexibility, gets in  Bronchi - are the passageways that connects your easily into the spleen and trap in there) windpipe to the lungs. It contains two main bronchi in your  foreign substances and defective red blood cells are right and left lung that divide and branch off into smaller removed from the blood by phagocytes in the red pulp of segments. the spleen (splenic cords and venous sinuses)  Lungs - major organ of the respiratory system which  limited reservoir for blood consist of the right and the left lung. The right lung is slightly  White pulp – lymphatic tissue surrounding the arteries larger that the left lung because the right lung has three within the spleen lobes while the left lung has 2 two lobes.  Red pulp – associated with the veins within the spleen  Alveoli - are tiny sacs that function as basic respiratory units. It is where the exchange of gases takes place. MARUHOM 18  TRANS: Module 1 DIGESTIVE SYSTEM  Kidneys – bean shaped organs about the size of a tightly  Oral Cavity clenched fist. Each kidney measures about 11cm long, 5cm  Throat (Pharynx) wide, and 3cm thick and weighs about 130g. These organs  Esophagus work constantly. They filter your blood and make pee, which  Small intestine your body then eliminates. You have two kidneys, one on  Large intestine either side of the back of your abdomen, just below your rib cage. Your kidneys work hard — they filter about 120 to 150 quarts (113.6 to 141.95 liters) of blood per day, which ORGANS OF THE DIGESTIVE SYSTEM produces about 1 to 2 quarts (0.95 to 1.95 liters) of pee Alimentary canal – tube extending from mouth to anus each day.  Mouth  Ureter – carry urine from kidneys to bladder  Pharynx  Urinary bladder – triangle shaped, hollow organ in the  Esophagus lower abdomen which stores urine, allowing urination to be  Stomach infrequent and controlled. Your bladder expands as it fills  Small intestine up. Most bladders can hold up to 2 cups (500 milliliters) of  Large intestine pee at a time.  Rectum and anal canal  Urethra - The urethra is the vessel responsible for transporting urine from the bladder to an external opening in the perineum. The male urethra is approximately 15- 20cm long. In addition to urine, the male urethra transports semen – a fluid containing spermatozoa and sex gland secretions. In females, the urethra is relatively short (approximately 4cm). It begins at the neck of the bladder, and passes inferiorly through the perineal membrane and muscular pelvic floor. The urethra opens directly onto the perineum, in an area between the labia minora, known as the vestibule. ACCESSORY ORGANS  Teeth  Tongue REPRODUCTIVE SYSTEM  Pancreas MALE REPRODUCTIVE ORGANS  Liver & biliary duct  Testicle - is the male reproductive gland or gonad in all  Gall bladder bilaterians, including humans.  Salivary glands  Epididymis - is a long, coiled tube that rests on the back of each testicle. It carries and stores the sperm cells