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BIOS255 Comprehensive – Complete
Study Guide
Negative feedback ✔Ans - A process in which the body senses a change and activates mechanisms that reverse it. Keeps a variable close to its set point. Negative feedback opposes original stimulus. MOST COMMON feedback loop. Examples of negative feedback ✔Ans - body temperature, blood pressure, glucose regulation Components of a feedback loop ✔Ans - stimulus, sensor, control center, effector Positive feedback ✔Ans - A type of regulation that responds to a change in conditions by initiating responses that will amplify the change. Takes organism away from a steady state. Enhances original stimulus Examples of positive feedback ✔Ans - birth, blood clotting, lactation epithelial tissue ✔Ans - Epithelial tissue consists of a sheet of closely adhering cells, one or more cells thick, with the upper surface usually exposed to the environment or to an internal space in the body. Epithelium covers the body surface, lines body cavities, forms the external and internal linings of many organs, and constitutes most gland tissue. epithelia ✔Ans - avascular (without blood vessels) —there is no room for them between the cells. Epithelia, however, usually lie on a vessel rich layer of connective tissue, which furnishes them with nutrients and waste removal what is beneath epithelial tissue? ✔Ans - a basement membrane that serves as an anchor to the connective tissue layer beneath
are epithelial tissues polarized? ✔Ans - epithelial cells establish an apical-basial polarity which results from the differential distribution of phospholipids, proteins complexes, and cytoskeletal components between the various plasma membrane domains reflecting their specialized functions CONNECTIVE TISSUE What is chondroitin sulfate and ✔Ans
- Chondroitin sulfate is the most common GAG (glycosaminoglycans) How are glycosaminoglycans charged? ✔Ans - GAGS are negatively charged, which attracts sodium and potassium ions, which in return causes them to absorb and retain water Where is chondroitin sulfate located in the body? ✔Ans - found in blood vessels and bones What role do glycosaminoglycans (GAGs) have ✔Ans - they regulate the water and electrolyte balance in tissues collagen fibers ✔Ans - provides flexibility and strength elastic fibers ✔Ans - Flexible and "stretchy" fibers that add elasticity to tissue reticular fibers ✔Ans - Fibers made of collagen fibers that are very thin and branched. interwoven what is the function of keratin in the epidermis? ✔Ans - The epidermal cells are packed with a tough protein keratin and linked by strong desmosomes that gives the epithelium, or skin, is durability merocrine (eccrine) glands ✔Ans - Sweat glands that function in evaporative cooling; widely distributed over the body surface; open by ducts onto the skin surface
subchondral bone, hyaline cartilage, a joint cavity, synovial lining, articular capsule, and supporting ligaments. what type of mobility is observed in a synovial joint ✔Ans - Synovial joints like the elbow knee and knuckle are freely mobile. Other joints such as the wrist and ankle bones have more limited mobility. Where is the sacroiliac joint located and which bones are found in this joint ✔Ans - Located between the iliac bones and the sacrum connecting the spine to the hips located below the waist where to dimples are visible Explain why the talocrural joint is classified as a hinge joint ✔Ans - This is also called the ankle joint it is considered a hinge joint because it's freely moving in one plane permitting dorsiflexion and plantarflexion of the foot What is the effect of acetylcholine attaching to its receptor ✔Ans - Binding with receptors can have different effects depending on the area of the nervous system that acetylcholine is affecting. Acetylcholine can cause an action potential, or it could activate a secondary messenger system end plate potential ✔Ans - The depolarization of the motor end plate on a muscle cell. BE ABLE TO BREIFLY EXPLAIN STEPS OF EXCITATION CONTRACTION ✔Ans - What is a sarcomere? ✔Ans - contractile unit of a muscle fiber difference between muscle twitch, incomplete tetanus, and complete tetanus ✔Ans - muscle twitch ✔Ans - the response of a muscle to a single brief threshold stimulus
incomplete tetanus ✔Ans - muscle fibers partially relax between contraction complete tetanus ✔Ans - no relaxation between contractions Locate biceps femoris, semitendinosus, semimembranosus ✔Ans - What muscles are part of the quadriceps group ✔Ans - Rectus femoris, vastus lateralis, vastus medialis, vastus intermedius Agonists ✔Ans - prime movers, primarily responsible for producing a particular movement Synergist ✔Ans - muscle that aids a prime mover in a movement and helps prevent rotation Antagonist ✔Ans - muscle that opposes or reverses a prime mover Describe the overall function of the nervous system ✔Ans - To maintain body homeostasis with electrical signals, provide for sensation, higher mental functioning and emotion response, and activate muscles and glands. Name the regions of the body innervated by the phrenic and sciatic nerves ✔Ans - Phrenic nerve innervates diaphragm. Sciatic nerve innervates muscles of the posterior thigh and indirectly innervates all the muscles of the leg and foot What are the functions of cerebrospinal fluid? ✔Ans - Cerebrospinal fluid acts as a shock absorber cushioning the brain against the skull 12 cranial nerves in order ✔Ans - 1. Olfactory
- Optic
- Oculomotor
- Trochlear
Hematocrit ✔Ans - erythrocytes How can hematocrit increase? ✔Ans - transfusion With blood types, what does the positive and negative refer to? ✔Ans - The Rh factor is an inherited protein that can be found on the surface of the red blood cell. If your blood type is positive, then your blood cells have the Rh protein. If your blood type is negative, then your blood cells lack the Rh protein. What does agglutination mean? ✔Ans - Antibodies bind to antigens and mark them, or the cells bearing them, for destruction. One method of antibody action is agglutination, in which each antibody molecule binds to two or more foreign cells and sticks them together tunica externa ✔Ans - outer layer of a blood vessel which connects it to surrounding tissues tunica media ✔Ans - The middle and thickest layer of tissue of a blood vessel wall, composed of elastic tissue and smooth muscle cells tunica intima ✔Ans - the innermost layer of a blood vessel What is the function of blood colloid osmotic pressure in net reabsorption pressure? ✔Ans - The pressure created by the concentration of colloidal proteins in the blood is called the blood colloidal osmotic pressure (BCOP). Its effect on capillary exchange accounts for the reabsorption of water. MAP equation ✔Ans - diastolic pressure + 1/3 pulse pressure Pulse pressure equation ✔Ans - systolic pressure - diastolic pressure Why do the AV valves open/close? ✔Ans - When atrial pressure is greater than ventricular pressure, the AV valves opens and blood flows through. When ventricular pressure rises
above atrial pressure, the blood in the ventricle pushes the valve cusps closed. Vascular resistance depends on ✔Ans - blood viscosity, total blood vessel length, vessel radius blood viscosity ✔Ans - more viscous = more resistance less viscous = less resistance vessel length ✔Ans - The farther liquid travels through a tube, the more cumulative friction it encounters Pressure and flow decline with distance vessel radius ✔Ans - vasoconstriction narrows vessel and forces blood through a narrower lumen, increasing peripheral resistance and blood pressure. vasodilation widens vessel, decreasing peripheral resistance and blood pressure What is the role of calcium in the contraction of ventricular tissue? ✔Ans - The calcium that enters the heart cell through the calcium ion channel activates the ryanodine receptor to release enough calcium from the sarcoplasmic reticulum to initiate heart muscle contraction. Cardiac output equation ✔Ans - CO = HR x SV Does more blood enter the ventricle during atrial diastole or atrial systole? ✔Ans - Blood flow into the coronary arteries is greatest during ventricular diastole when aortic pressure is highest and it is greater than in the coronaries. How does pH & body temperature affect the affinity of hemoglobin for oxygen? ✔Ans - increased temperature decreases the affinity of hemoglobin for oxygen. increase in pH increases hemoglobin's affinity for oxygen If the innate and immune system fail to remove a pathogen, what aspect of the immune system takes over? ✔Ans - the
Its main function is to send signals to the muscles that control respiration to cause breathing to occur What are the effects of surfactant on alveoli surface area and water tension within the alveoli? ✔Ans - increased surface tension increases cohesion within the alveoli, pulling the alveoli closed. The alveolar cells produce a specialized liquid, surfactant, that decreases the surface tension in the airways reducing the amount of energy required to expand the lungs. Explain the difference between internal and external respiration. ✔Ans - External respiration is the exchange of gases with the external environment, and occurs in the alveoli of the lungs. Internal respiration is the exchange of gases with the internal environment, and occurs in the tissues. The actual exchange of gases occurs due to simple diffusion. Essay Questions- variables influencing the affinity of oxygen with hemoglobin and variation in pulmonary capillary and active muscle Flu like symptoms after the flu vaccine- why do they happen?? ✔Ans -
