BIOL 3701 Lesson 1: Tissues and Systems PDF

# BIOL 3701 Lesson 1: Tissues and Systems ## Lesson Objectives: 1. Use correct anatomical terminology to describe anatomical position, planes, relationships, body movements, and bony markings. 2. Describe the four basic tissues and their subclassifications, and give examples of each. 3. Define...

# BIOL 3701 Lesson 1: Tissues and Systems ## Lesson Objectives: 1. Use correct anatomical terminology to describe anatomical position, planes, relationships, body movements, and bony markings. 2. Describe the four basic tissues and their subclassifications, and give examples of each. 3. Define three main classes of joints and distinguish between six types of synovial joints, giving examples of each. 4. Compare the major systems related to musculoskeletal anatomy including skeletal, articular, muscular, cardiovascular, and nervous systems in terms of function, classification, components, and organization. 5. Identify selected features of the minor systems including respiratory, gastrointestinal, urinary, reproductive, endocrine, and integumentary systems. 6. Define the boundaries and walls of the major body cavities including the thorax, abdomen, and pelvis, and given a diagram, be able to identify major contents. 7. Identify muscles, ligaments, cartilage, joint surfaces, nerves, and blood vessels in a chicken leg. ## Topic 1: Anatomical Terminology - **Planes:** coronal, sagittal, transverse (horizontal, axial). - **Directional Terms:** anterior/posterior, medial/lateral, superior/inferior, proximal/distal, rostral/caudal, superficial/deep. - **Action Terms:** abduction/adduction, lateral rotation/medial rotation, flexion/extension, elevation/depression, spinal flexion/spinal extension, pronation/supination, circumduction, dorsiflexion/plantar flexion, eversion/inversion, retraction/protraction, opposition (thumb). ## Topic 2: The Four Basic Tissues of the Body The body is composed of cells (single living units) and the material that they produce - nothing else. ### Tissues are collections of similar cells working in a common function and the extracellular matrix they produce. - Tissues are combined into functional units called organs - Epithelium, nerve, and muscle tissues are composed of one cell type - connective tissues are more complex. - The cells produce a basement membrane as a base of extracellular material to which they are anchored. ### (1) Epithelial Tissue: Covers the body surfaces, lines the body cavities, ducts or organs and glands, vasculature, forms secretory portions of glands. Epithelial cells accomplish this function by forming clusters or sheets held together by intercellular junctions. #### a. Simple epithelium: one cell layer in thickness 1. **Simple squamous:** lines body cavities and vasculature, offering a barrier to transport or functioning as an exchange system, often by simple diffusion. 2. **Simple cuboidal:** lines ducts of glands and kidney tubules, offering a passageway with or without the ability for absorption and secretion. #### b. Stratified epithelium: two or more cell layers in thickness 1. **Pseudostratified:** trachea, bronchi of the lungs, and ductus deferens, offering a passageway with or without barrier or secretory functions. 2. **Stratified Squamous:** the skin, oral cavity, esophagus, and vagina, offering a protective surface; the skin may have a protective layer of keratin overlying the epithelium. 3. **Stratified cuboidal:** ducts of sweat glands and other large exocrine glands, offering a conduit and/or a barrier to transport. 4. **Stratified Columnar:** large ductions of exocrine glands, offering a conduit and barrier. 5. **Transitional:** lines the urinary system, offering a conduit and the ability to distend. ### (2) Nervous Tissue Two classes of cells: - **Neuron:** conducts information Neurons communicate with one another through synapses that link one neuron to the next to create pathways that conduct information through the body. The brain consists of a collection of millions of neurons that receive information for the periphery, and respond to that sensory information through motor instructions. CNS = brain, cerebellum, and spinal cord - **Glial cells:** group of cells which provide support for neurons ### (3) Muscle Tissue - Skeletal muscle is divided into bundles or fascicles. These fascicles are composed of fibers. The fibers are composed of myofibrils, and myofibrils contain myofilaments. - The structure of skeletal muscle begins with contractile proteins (actin and myosin) assembled to form myofilaments that are grouped together into contractile units called myofibrils. Myofibrils (contractile protein nits) are organized in parallel, in repeating units called sarcomeres that generally extend the full length of the muscle. There are hundreds of myofibrils in a parallel that are the contractile units within a single multinucleated muscle cell called a myofibre. The individual myofibres are covered by endomesium. Myofibrils are grouped to form fascicles. The fascicles are surrounded by connective tissue called paramesium. Groups of multiple fascicles are then combined and surrounded by a single layer called epimesium to form a single muscle. - Increased number of myofibrils within the muscle cells (not increase in number of muscle cells = mm. becoming stronger. **Muscle fascicles:** which are surrounded by a connective tissue sheath known as the perimysium; epimysium is the connective tissue heath that surrounds multiple fascicles to form a complete muscle belly. **Muscle fibers:** which are composed of a muscle cell that is syncytium because it is multinucleated (the muscle fibers are surrounded by the endomysium). **Muscle myofibrils:** which are longitudinally orientated and extend the full length of the muscle fiber. **Muscle myofilaments:** which are the individual myosin (thick filaments) and actin (thin filaments) that slide over one another during muscle contraction. ### (4) Connective Tissue: Function to support, transport, store, immune defence, and thermoregulation. #### a. Connective tissue proper: includes loose and dense connective tissue arranged in either an irregular or regular formation. 1. **Loose irregular connective tissue:** found under epithelia lining both the body's surface and its internal organ systems. 2. **Dense irregular connective tissue:** many fibers but few cells and includes tendons, ligaments, the submucosa, and reticular layers that offer support. 3. **Dense regular connective tissue:** - **Tendons =**bundles of dense regular connective tissue, arising from the end of skeletal muscles and attaching to bone. - **Ligaments =**generally short, strap-like structures, stabilizing and providing stability to joints. #### b. Specialized connective tissue: includes cartilage, bone, adipose tissue (fat), hemopoietic tissue, blood, and lymph. 1. **Cartilage:** 3 types - fibrous, elastic, and articular cartilage. Articular cartilage is the most common and forms the template for developing bone and the covering of articular surfaces within the joint. The cartilage producing cells, chondrocytes, produce an ECM which is primarily a gel of fluid and collagen. #### c. Fibers: 1. **Collagen fibers:** flexibility and strength. 2. **Elastic fibers:** flexibility and retain shape if stretched. 3. **Reticular fibers:** thinner collagen fibers that provide strength (least common). ## Topic 3: Major & Minor Systems of the Body ### (1) Joints #### a. Solid Joints: No cavity and the components are held together by connective tissue. 1. **Fibrous joints** - Sutures, gomphoses, syndesmoses 2. **Cartilaginous joints** - Synchondroses and symphyses #### b. Synovial Joints: Skeletal elements are separated by a cavity (articular cavity). Also a layer of hyaline cartilage covers the articulating surfaces, has a joint capsule consisting of an inner synovial membrane (produces synovial fluid) and an outer fibrous membrane (surrounds and stabilizes the joint). 1. **Plane:** allow sliding or gliding movements when one bone moves across the surface of another. - Acromioclavicular joint. 2. **Hinge:** allow movement around one axis that passes transversely though the joint (flexion and extension). - Ex: elbow (humero-ulnar) joint. 3. **Pivot:** allow movement around one axis that passes longitudinally along the shaft of the bone; permits rotation. - Atlanto-axial joint. 4. **Bicondular or condular:** bicondylar allow movement mostly in one axis limited rotation around second axis (knee joint) and condylar allows movement around two axes that are at right angles to each other (flex, extension, ab, ad) (wrist joint). 5. **Saddle:** allow movement around 2 axes that are at right angles. - Carpometacarpal joint of thumb. 6. **Ball and socket:** allow movement around multiple aces. - Hip joint. ## Major Systems: ### (2) Muscular System (Skeletal Muscle) - **Skeletal Muscle:** contraction typically results in movement between bones at a joint but some muscles function to stabilize the body cavities or support organs (most vital is diaphragm which serves to increase and decrease the size of the thoracic cavity resulting in inspiration and expiration of air to and from the lungs). ### (3) Cardiovascular System - **Functions** in the organization of vessels that distribute blood to (arteries, oxygenated) and from (veins, deoxygenated blood) body tissues though the pumping action of the heart. Also distributes blood cells which serve to protect, defend and repair the body tissues. - **Capillaries** connect the arteries and the veins and are the smallest of blood vessels and are where oxygen, nutrients and wastes are exchanged within the tissues. - **Contains** the heart, arterial and venous systems. ### (4) Lymphatic System - **Functions** to circulate immune cells throughout the body and drains away excess tissue fluid. Also, important function in moving cancer cells from the primary cancer site to secondary sites. - Head and neck lymph drain into thoracic duct. - Right upper body right thoracic duct - Remaining areas of body left thoracic duct ### (5) Nervous System - **Consists** of neurons and their supporting cells that integrate communication within the nervous system. They function to receive sensory info, integrate that info, and produce the necessary response. We will study peripheral NS (receives sensory info from skin, connective tissue, joints, innervation skeletal muscles). - **Divided** into CNS and PNS - PNS motor and sensory nerves that make up the mixed somatic nerves that supply the trunk, upper and lower limbs. Also the cranial nerves that supply the head and neck ## Minor Systems: - Respiratory System - Gastrointestinal System - Begins at the oral cavity and ends at the anal canal. - Oral cavity pharynx esophagus stomach small intestine large intestine. - Contains the associated glands: salivary glands, liver, gallbladder, pancreas. - Urinary System - Includes: kidneys, ureters, urinary bladder, and urethra - Reproductive System - Female: - Ovaries, Uterine Tubes (fallopian tubes), Uterus, Vagina. - Male: - Ductus (vas) deferens, Testis, Epididymis, Prostate gland, Seminal vesicle. - Endocrine System - Integumentary System - Skin: the largest “organ” in the body. Protects ya ## Topic 4: Body Cavities - Cranium - Thoracic Cavity - Comprised of 3 major compartments: L & R Pleural Cavity (each surrounding a lung and the Mediastinum mediastinum houses the heart and great vessels. - Functions: Breathing, protection of vital organs, conduit. - Mediastinum: contains the heart, esophagus, trachea, major nerves, and major systemic blood vessels. - Superior mediastinum - Contains the arches of the great vessels as they leave or enter the heart and the trachea which divides into the left and right main bronchus. - Inferior mediastinum - Anterior - Middle - Contains the heart - Posterior - Contains great vessels (aorta and vena cava) - The Pleural Cavities: what happens in one, doesn't necessarily happen to the other. They extend above the level of rib 1, and it involves the root of the neck because the apex of each lung extends there. - Situated on either side of the mediastinum. - House the lungs and creates the conditions such that excursion of the thoracic cage results in the inspiration and expiration of breathing. - Abdominopelvic cavities - Functions: house and protect the viscera of the GI system and urogenital system. The contents of the abdominal cavity and pelvis are enclosed superiorly by the pulmonary diaphragm and supported inferiorly by the pelvic diaphragm ## Lesson 1 Level of Detail - Difference between regional and systemic anatomy - Regional: learning one region of the body in isolation. As a result, all systems in the region are learned together. - Systems: looking at a complete system to learn its organization throughout the body. - Classification of tissue - Epithelial - Muscle - Cardiac muscle - Smooth muscle - Striated muscle - Nervous - Neuron cells - Glial cells - Connective - Connective tissue proper - Loose irregular connective tissue - Dense irregular connective tissue - Dense regular connective tissue - Specialized connective tissue - Bone - Cartilage - Adipose tissue - Hemopoietic tissue - Blood - Lymph - Anatomical position - Facing forward, arms by sides, palms facing forward (supination), fingers straight and the palms in the same plane as the fingers, feet slightly apart with toes pointing forward. - Anatomical terminology (directional terms and bony landmarks) - Directional terms: - Anterior and posterior - Medial and lateral - Superior and inferior - Proximal and distal - Rostral and caudal - Superficial and deep - Action terms: - Abduction and adduction - Lateral and medial rotation - Flexion and extension - Elevation and depression - Spinal flexion and spinal extension - Pronation and supination - Circumduction - Dorsiflexion and plantarflexion - Eversion and inversion - Retraction and protraction - Opposition (thumb) - Types and functions of bones - Bones of axial and appendicular skeleton (name and location) - Classification of joints - Synovial Joints - Plane joint - Hinge joint - Pivot joint - Bicondylar or condylar joint - Saddle joint - Ball and socket joint - Solid Joints - Fibrous joints - Cartilaginous joints - Symphysis - Organs of each system (just a list) - Cardiovascular System - Heart - Arteries - Veins - Nervous System - CNS - Brain - Brainstem - Cerebellum - Spinal cord - Motor nerves - Sensory nerves - Cranial nerves - PNS - Differences between arteries and veins - Arteries: supply blood to the body from the heart - Veins: supply blood to the heart from the body **Dermatomes and myotomes are very important, you need to know them in detail. They are put on lesson 1, but you will understand and study them more and more as you will go through other lessons of the course.**