Nini A&P 1 PDF Class Notes - Anatomy & Physiology

Class Notes Date: 1/27/2024 A&P: Anatomy and Physiology I Chap:1,2,8,9 Cohort 29 Chapter 8 Skeletal system List the functions of the skeletal system and the classification of bones by size and shape. The skeletal system has several...

Class Notes Date: 1/27/2024 A&P: Anatomy and Physiology I Chap:1,2,8,9 Cohort 29 Chapter 8 Skeletal system List the functions of the skeletal system and the classification of bones by size and shape. The skeletal system has several key functions: ​ Support - Bones provide structural support and shape to the body. ​ Protection - Bones shield and protect vital organs like the brain, heart, and lungs. ​ Movement - Bones and skeletal muscles allow for body movement. ​ Blood cell production - Red and white blood cells are made in bone marrow.  2 ​ Mineral storage - Bones store important minerals like calcium and phosphorus. Bones are classified by their size and shape into four main types: ​ Long bones - Have a long cylindrical shaft, like the femur and humerus. ​ Short bones - Roughly cube-shaped, like those in the wrists and ankles. ​ Flat bones - Thin and curved, such as ribs, skull, and shoulder blades. ​ Irregular bones - Complex shapes that don't fit other categories, like vertebrae. Differentiate between the composition and location of compact and spongy bone. ​ Compact bone is dense and solid, forming the outer layer. ​ Spongy bone has a porous, honeycomb structure inside bones, containing bone marrow. ​ Compact bone provides strength and protection, while spongy bone contains bone marrow for blood cell production and storage of minerals.  3 Describe the structure of a long bone To remember the structure of a long bone easily: ​ Diaphysis - The long shaft in the middle ​ Epiphysis - The rounded ends ​ Metaphysis - The area connecting shaft to ends ​ Epiphyseal plate - The growth plate in children between epiphysis and metaphysis Describe the roles of osteoblasts and osteoclasts, and how bones grow in length and width ​ Osteoblasts build new bone, while osteoclasts break down old bone. For length growth, the epiphyseal plate between the epiphysis and metaphysis allows new bone to form. For width growth, osteoblasts on the outer periosteum surface create a more compact bone, while osteoclasts on the inner endosteum surface expand the marrow cavity. List the bones of the axial skeleton and label important landmarks on selected bones. Axial Skeleton Bones: -Skull: Frontal, parietal, occipital, temporal, sphenoid, ethmoid Landmarks: Orbit, zygomatic, mandible Hyoid bone -Vertebral Column: Cervical (7), thoracic (12), lumbar (5), sacrum, coccyx  4 Landmarks: Vertebral body, spinous process, transverse process -Rib Cage: Sternum (manubrium, body, xiphoid process), ribs (12 pairs) *Remember key words like "skull", "hyoid", "vertebrae", "ribs" for the axial bones. Visualize the skull's orbit and mandible, the vertebrae's processes, and the sternum's parts.* List the bones of the appendicular skeleton and label important landmarks on selected bones. Appendicular Skeleton Bones: -Pectoral Girdles: Clavicle, scapula (acromion, spine, glenoid cavity) -Upper Limbs: Humerus (head, greater/lesser tubercles), radius, ulna, carpals, metacarpals, phalanges -Pelvic Girdle: Hip bones (ilium, ischium, pubis), sacrum, coccyx -Lower Limbs: Femur (head, greater/lesser trochanters), patella, tibia, fibula, tarsals, metatarsals, phalanges List the main types and functions of joints and describe the type of joint movement Joint types: ​ Fibrous (immovable,rigid) ​ Cartilaginous (semi-movable/rigid) ​ Synovial (freely movable) Movements: ​ Hinge (knee/elbow - bend/straighten) ​ Ball-and-socket (hip/shoulder - rotate) ​ Pivot (neck - turn)  5 ​ Gliding (wrist/ankle - slide) Chapter 9 Muscular System Identify three types of muscle tissue The three types of muscle tissue are: 1) Skeletal (striated, voluntary) - Attached to bones for voluntary movement. 2) Cardiac (striated, involuntary) - Found in the heart walls, controls heartbeat. 3) Smooth (visceral, involuntary) - Found in internal organs like stomach and blood vessels. Compare the structure of a whole muscle and the structure of a single muscle fiber Whole Muscle: ​ Epimysium (outer covering) ​ Fasciculi (bundles of muscle fibers) ​ Perimysium (covering fasciculi) Single Muscle Fiber: ​ Endomysium (innermost covering) ​ Myofibrils (contractile units)  6 ​ Sarcomeres (actin and myosin filaments) Describe the sliding filament mechanism of a muscle contraction The sliding filament mechanism of muscle contraction can be simplified as: 1) Calcium enters the muscle fiber 2) Calcium binds to troponin, changing the actin shape 3) This exposes myosin binding sites on actin 4) Myosin heads bind to the exposed actin sites 5) Myosin heads pull the actin filaments inward 6) This causes the actin filaments to slide over the myosin 7) The sliding shortens the muscle fiber, creating contraction 8) Calcium is pumped back out to relax the muscle *The key is the sliding of the overlapping actin and myosin filaments driven by calcium and the myosin cross-bridge cycling.* Explain the role of calcium and adenosine triphosphate (ATP) in muscle contraction. ​ Calcium ions initiate muscle contraction by binding to troponin, exposing myosin binding sites on actin. ATP provides the energy for myosin heads to bind to actin and pull the filaments, generating the contraction. ATP is constantly regenerated from cellular energy sources to sustain contractions.  7 *Calcium is like a key that unlocks the door for your muscles to squeeze. ATP is like the energy drink that gives your muscles the power to keep squeezing. Without calcium, the door stays locked and your muscles can't contract. And without ATP, your muscles get tired quickly and can't keep squeezing strongly. Calcium unlocks and ATP energizes your muscles to work properly.* Describe the relationship between skeletal muscles and nerves, including the motor unit and its relationship to recruitment and the events that occur at the neuromuscular junction. ​ Your muscles are like little squeezing machines that help you move. But they need help from your nerves to know when to squeeze. The nerves are like messengers that tell the muscles when it's time to squeeze or relax. ​ Each nerve talks to a bunch of muscle squeezing machines, and that whole group is called a motor unit. When you need to squeeze harder, more motor units get called in to help out. It's like calling in more friends to help you lift something heavy. ​ At the place where the nerve meets the muscle, called the neuromuscular junction, the nerve releases a special chemical messenger called acetylcholine. This messenger tells the muscle squeezing machines to start squeezing by letting in calcium, which is like giving the machines a power boost to contract. ​ So in short, your nerves tell your muscles when to squeeze by sending chemical messengers, and more nerves get involved for stronger squeezes. The muscles are the squeezing machines, but the nerves are the bosses telling them what to do! Discuss muscle responses: single fiber and whole muscle: Single fiber  8 Define twitch and tetanus. ​ Twitch = brief contraction from one stimulus ​ Tetanus = sustained contraction from rapid, repeated stimuli before relaxation Whole Muscle Identify the sources of energy for muscle contraction. ​ ATP = immediate energy source ​ Phosphocreatine = quick ATP replenishment ​ Glucose breakdown = ATP supply with low oxygen Trace the sequence of events from nerve stimulation to muscle contraction. ​ Nerve signal triggers calcium release ​ Calcium allows myosin to bind actin ​ Myosin pulls actin filaments inward, shortening muscle fibers ​ Shortened overlapping fibers cause overall muscle contraction Define muscle terms and state the basis for naming muscles Muscle terms: ​ Origin - Attachment point on stationary bone ​ Insertion - Attachment on movable bone ​ Belly - Fleshy, contracting part Muscle naming: ​ Based on location, shape, size, number of origins, action, or attachments Examples: Biceps (two origins), Rectus (straight), Deltoid (delta shape)  9 Identify and list the actions of the major muscles. Major muscle actions: ​ Deltoid - Arm abduction/flexion ​ Biceps - Elbow flexion ​ Triceps - Elbow extension ​ Quadriceps - Knee extension ​ Hamstrings - Knee flexion ​ Gastrocnemius - Plantar flexion (pointing toes) ​ Abdominals - Trunk flexion ​ Erector spinae - Trunk extension Chapter 1 Introduction to The Human Body Define the terms anatomy and physiology ​ Anatomy is the study of the structure and shape of the body and its parts. ​ Physiology is the study of how the body and its parts function or work.  10 List the levels of organization of the human body. The levels of organization of the human body from smallest to largest are: ​ Atoms ​ Molecules ​ Organelles ​ Cells ​ Tissues ​ Organs ​ Organ systems ​ Organism Describe the 12 major organ systems. The 12 major organ systems of the human body are: 1. Integumentary system (skin, hair, nails) 2. Skeletal system (bones, cartilage, ligaments) 3. Muscular system (skeletal, cardiac, smooth muscles) 4. Nervous system (brain, spinal cord, nerves) 5. Endocrine system (hormones from glands like thyroid, pancreas) 6. Cardiovascular system (heart, blood vessels) 7. Lymphatic system (lymph nodes, vessels, tissues) 8. Respiratory system (nose, lungs, diaphragm) 9. Digestive system (mouth, stomach, intestines) 10. Urinary system (kidneys, bladder, urethra) 11. Reproductive system (ovaries, testes, uterus) 12. Immune system (white blood cells, lymph organs)  11 *Each system plays a vital role in maintaining homeostasis and overall health by working together in harmony.* Define homeostasis ​ Homeostasis refers to the maintenance of a relatively stable internal environment within the body, even when the external environment changes. It is the process of keeping various physiological conditions like temperature, pH, fluid balance, and nutrient levels within a normal range to allow the body's cells and systems to function properly. Describe the anatomical position ​ The anatomical position is the standard reference position used to describe the locations of body structures. It involves standing upright, with feet flat and slightly apart, arms at the sides with palms facing forward, and head, eyes, and toes pointing straight ahead.  12 List common terms used for relative positions of the body. Here's an easy way to remember common terms for relative body positions: Superior - Above Inferior - Below Anterior - Front Posterior - Back Medial - Toward midline Lateral - Away from midline Proximal - Closer to Distal - Further away from Superficial - Closer to surface Deep - Further from surface *Visualize yourself in an anatomical position to apply these directional terms properly.*  13 Describe the three major planes of the body. To easily remember the three major planes of the body, think of slicing a loaf of bread: Sagittal plane - Slices the body vertically from front to back, dividing it into left and right sides. Coronal plane - Slices the body vertically from side to side, dividing it into front and back portions. Transverse plane - Slices the body horizontally, dividing it into upper and lower portions. List anatomical terms for quadrants and regions of the body To easily remember anatomical quadrants and regions: Quadrants: RUQ - Right Upper Quadrant LUQ - Left Upper Quadrant RLQ - Right Lower Quadrant LLQ - Left Lower Quadrant Regions: Umbilical - Around navel Hypogastric - Below umbilical Epigastric - Above umbilical  14 Hypochondriac - Upper abdomen, below ribs Lumbar - Back, around loins Iliac - Lower abdomen, over hips Describe the major cavities of the body. The major cavities of the body are: Dorsal: Cranial cavity - Contains the brain, located in the skull.(The attic, housing the brain) Spinal cavity - Contains the spinal cord, running through the vertebral column. (The hallway, containing the spinal cord) Ventral Thoracic cavity - Contains the heart, lungs, and related structures. Divided into the pleural cavities for the lungs and the mediastinum.(The living room, with the heart and lungs) Abdominal cavity - Contains the stomach, liver, gallbladder, spleen, pancreas, and most of the intestines.(The kitchen, holding digestive organs) Pelvic cavity - Contains the urinary bladder, internal reproductive organs, and the rectum. Part of the larger abdominopelvic cavity.(The basement, with reproductive organs) *These cavities house and protect the body's vital organs, with the thoracic, abdominal, and pelvic cavities comprising the ventral cavity.*  15 Chapter 2 Basic Chemistry Define the terms matter, element, and atom, and do the following: ​ Matter is anything that occupies space and has mass. ​ An element is a pure substance that cannot be broken down into simpler substances by chemical means. ​ An atom is the smallest unit of an element that retains its properties. List the four elements that comprise 96% of body weight ​ Oxygen ​ Carbon ​ Hydrogen ​ Nitrogen Describe the three components of an atom ​ Protons (positively charged particles in the nucleus) ​ Neutrons (neutral particles in the nucleus) ​ Electrons (negatively charged particles orbiting the nucleus) Describe the role of electrons in the formation of chemical bonds ​ Electrons play a crucial role in the formation of chemical bonds. The outermost electrons, called valence electrons, can be shared or transferred between atoms to form ionic or covalent bonds. This bonding allows atoms to achieve a stable electron configuration and form molecules.  16 Differentiate among ionic, covalent, and hydrogen bonds. ​ Ionic bond: Caused by a transfer of electrons between atoms ​ Covalent bond: Involves a sharing of electrons by the outer shells of the atoms ​ Hydrogen bond: An intermolecular attraction, not caused by transfer of electrons or sharing of electrons by outer shell of the atoms Explain ions, including the differences among electrolytes, cations, and anions ​ Ions: Atoms or groups of atoms that carry an electrical charge Two types of ions ​ Cations: Positively charged ​ Anions: Negatively charged ​ Electrolytes: Form ions when dissolved in water Explain the difference between a molecule and a compound, and list five reasons why water is essential to life. Molecule vs Compound: ​ Molecule - Two or more atoms chemically bonded together (e.g. H2O) ​ Compound - Two or more different elements chemically bonded (e.g. H2O is a compound of hydrogen and oxygen)  17 5 Reasons Water is Essential: ​ Medium for biochemical reactions ​ Transports nutrients and wastes ​ Lubricates joints ​ Regulates body temperature ​ Maintains blood volume Explain the role of catalysts and enzymes ​ Catalysts and enzymes speed up reactions by lowering the energy needed. Catalysts are inorganic, enzymes are biological proteins. They provide an alternative pathway requiring less activation energy, increasing the rate of reactions without being used up. Differentiate between an acid and a base, and define pH ​ An acid is a substance that releases hydrogen ions (H+) when dissolved in water ​ A base releases hydroxide ions (OH-) ​ pH is a scale that measures the acidity or basicity of a solution. It ranges from 0 to 14, with 7 being neutral. Solutions with a pH less than 7 are acidic, and those with a pH greater than 7 are basic. The pH value indicates the concentration of hydrogen ions present. ​ List the six forms of energy and describe the role of adenosine triphosphate (ATP) in energy transfer ​ The six forms of energy are chemical, radiant, electrical, thermal, mechanical, and nuclear. ATP is the energy currency of cells. It stores and transfers energy from food molecules to power cellular  18 processes like muscle contraction, active transport, and biosynthesis. ATP releases energy when its phosphate bonds are broken, driving reactions forward. Differentiate between a mixture, solution, suspension, colloidal suspension, and a precipitate. 1.​ Mixture: Two or more substances mixed together, but they don't chemically bond. They can be separated easily (e.g., salad, trail mix). 2.​ Solution: A type of mixture where one substance dissolves completely in another (e.g., sugar in water). It looks uniform and you can't see the individual parts. 3.​ Suspension: A mixture where particles are large and don't dissolve, so they float and can settle over time (e.g., muddy water). You can see the particles if you wait. 4.​ Colloidal Suspension: Similar to a suspension, but the particles are small and don’t settle easily. The mixture looks uniform but you can still sometimes see tiny particles under a microscope (e.g., milk, fog). 5.​ Precipitate: A solid that forms from a liquid when two substances react together (e.g., when you mix two clear liquids and a solid forms at the bottom). Just think: ​ Mixture: Anything mixed together. ​ Solution: A dissolved mix. ​ Suspension: Particles that float. ​ Colloid: Tiny floating particles that stay suspended. ​ Precipitate: Solid formed from a reaction. 19