MCB 32 Fall, 2000
Topics for Review for Midterm #2
Overall: You are responsible only for material covered in class.
General
Relative concentrations of Na+, Cl-, K+, Ca2+ and pH in blood and inside cells.
Define homeostasis and negative feedback.
Endocrine Physiology and Second Messengers
Functionally define: Autocrine, paracrine and endocrine; mechanism of action of steroid hormone
(DNA, RNA, protein synthesis, Fig. 5.3); kinase and phosphatase; second messenger; receptor, G
protein and adenylate cyclase; cAMP; protein kinase A (Fig. 5.4); phosphodiesterase; phospholipase;
phospholipid; inositol trisphosphate; IP3 receptor; Ca pump in the endoplasmic reticulum; roles of ATP
in generation of cAMP and phosphorylation of proteins by kinases
Know the following hormones, including sites of synthesis, whether they are steroids or amino acid
derivatives or proteins/peptides, regulation of release and effects on tissues of the body: epinephrine,
insulin, glucagon, parathyroid hormone, TSH, TRH, thyroid hormones (T3 and T4), cortisol, ACTH,
CRH.
Understand feedback control of glucose concentration in the blood by insulin and glucagon (Fig. 5.7)
and Ca concentration by parathyroid hormone (Fig. 5.21 and 5.22), and contrast that with mechanism of
regulation of cortisol levels and thyroid hormone levels in the blood (Figs 5.10 and 5.17). Know the
functions of thyroid hormone (increased metabolism, oxygen consumption, protein catabolism) and
cortisol (“permissive” hormone; increased [glucose], anti-inflammatory).
Define and/or know the anatomical structure and function of: hypothalamus, anterior pituitary, posterior
pituitary, adrenal medulla, adrenal cortex, thyroid gland, thyroglobulin (Figs. 5.12, 5.15, 5.16)
Muscle Physiology
Composition and function of bones, ligaments and tendons (Figs 6.6, 6.7, 6.8). Define osteoblast and
osteoclast.
Define motor nerve and motor unit (Fig. 6.18); hypertrophy vs hyperplasia; multinucleate (Fig. 6.12); A
bands, I bands and z-lines; T-tubules and sarcoplasmic reticulum (Fig. 6.15); sliding filament model
(Fig. 6.14 and 6.19)
List types of muscle based on myosin ATPase activity and energy production mechanisms
(mitochondria-aerobic vs glycolysis-anaerobic).
Know general reactions that lead to ATP production: creatine kinase reaction, glycolysis, oxidative
phosphorylation (Table 6.2)
Sequence of events at the neuromuscular junction and triggering of muscle contraction: action potential,
release of neurotransmitter (ACh), stimulation of action potential in the muscle, excitation of T tubules
(including dihydropyridine receptor), activation of ryanodine receptor and release of Ca, role of troponin
and tropomyosin, ATP cycling (Fig. 6.20).
Know roles of ATP in generating muscle contraction: Use by Na/K- and Ca-ATPases, role in myosin
cross bridge cycling
What is the rigor state? How do you know that during fatigue [ATP] in the cytosol may be lower than
normal, but it is not zero?
Comparison of skeletal, cardiac and smooth muscle with regard to: sarcomeres and presence of
sarcoplasmic reticulum, actin and myosin, electrical activity, electrical coupling of one cell to the next,
excitation-contraction coupling, contraction (sustained vs periodic contractions, thin filament regulation
vs thick filament regulation), regulation by nerves (motor nerves and motor units vs autonomic nerves
and hormones). (Figs 6.22, 6.23, 6.26, 6.28, 6.29; Table 6.3)
Neurotransmitters released by somatic motor nerves vs autonomic nerves.
Cardiovascular Physiology
Anatomy of heart and systemic and pulmonary circulations. Know sequence of blood flow through the
different structures (Fig. 8.1, Fig 8.4).
Function of key structures in heart (cardiac muscle; SA and AV nodes; conduction pathway for action
potentials) and vessels (connective tissue, including valves; smooth muscle)
Sequence of heart functions: atrial filling and contraction; ventricular filling and contraction; heart
sounds; systole (systolic pressure) and diastole (diastolic pressure) (Fig. 8.10)
SA node generation of action potentials and alterations with sympathetic and parasympathetic nerve
stimulation. Figs 6.23 and 8.7 and Highlight 8.1
Skeletal muscle vs cardiac muscle structure (actin, myosin, tropomyosin, troponin; sarcomeres; SR;
tissue structure) and membrane permeabilities to ions, including action potential; refractory periods;
control by skeletal vs autonomic (sympathetic and parasympathetic) nerves; role of venous return
Control of blood flow (by changes in contraction of smooth muscle and precapillary sphincters) at tissue
level by metabolic waste products (e.g., lactic acid, CO2 and AMP). Magnitude of changes in blood
flow through blood vessels with dilation by factor of two. Figs. 9.13 and 9.14). Myogenic regulation.
Capillary fluid exchange controlled by blood pressure and plasma osmotic pressure (due to plasma
proteins), and effects of changes in either of these. Lymph vessel collection of excess tissue fluid.
Causes of edema (imbalance of filtration vs osmosis). Figs 9.15 and 9.16.
Blood pressure regulation: baroreceptors (aortic arch and carotid sinus), cardiovascular center (medulla
oblongatta), sympathetic and parasympathetic effects, including neurotransmitters. Effects of
hemorrhage on blood pressure, negative feedback regulation, changes in capillary fluid dynamics. Figs
9.18 and 9.19
Effects of exercise on heart rate and stroke volume and peripheral resistance. Arterial blood pressure
increases only slightly if at all during relatively large increases in blood flow/cardiac output.