Hormones & Glands
A hormone influences the activity of only those tissue cells that have ________ for it.
Receptors
Describe the composition of blood.
-Liquid plasma (55% of whole blood)
-RBCs (45% of whole blood)
-WBCs (+ platelets = <1% of whole blood)
-Platelets (+ WBCs = <1% of whole blood)
What is the name of the receiving chambers of the heart, and what is the name of the discharging chambers of the heart?
Atria = receiving chambers
Ventricles = discharging chambers
(4 chambers of the heart in total)
______ carry blood away from the heart, while ______ carry blood toward the heart.
Arteries, veins
What are tropic hormones, name the four you are required to know and name the endocrine gland that releases them.
Tropic hormones regulate the secretory action of other endocrine glands.
4 anterior pituitary tropic hormones: TSH, ACTH, FSH & LH
What are the 3 functions of blood?
1. Distribution: transports O2, metabolic wastes, hormones
2. Regulation: maintains appropriate body temp, normal pH & adequate fluid volume
3. Protection: prevents infection (antibodies & WBCs)
Name the 4 valves of the heart and the function of these valves.
AV Valves: Tricuspid valve, bicuspid (mitral) valve
SL Valves: Pulmonary SL valve, aortic SL valve
Function: to prevent the backflow of blood
Why are veins considered "blood reservoirs"?
They contain 60% of the body's blood supply.
Explain the difference between up-regulation and down-regulation.
Up-regulation: target cells form more receptors in response to low levels of a hormone (hyposecretion)
Down-regulation: target cells lose receptors in response to high hormone concentrations (hypersecretion)
What is the difference between an antibody and an antigen?
Antibody: protein substances that protect against foreign antigens -> coat antigens (do not kill them)
Antigen: something the body perceives as foreign; generates an immune response
Name the double-walled sac that encloses the heart, and the 3 layers of the heart wall.
3 layers: Epicardium (visceral layer of serous pericardium), Myocardium (cardiac muscle layer), Endocardium (simple squamous epithelium)
What are the 3 important sources of peripheral resistance?
1. Blood viscosity
2. Total blood vessel length
3. Blood vessel diameter
List the steps of amino acid-based hormone action.
1. Amino acid hormones bind to receptor.
2. Binds to a G protein.
3. G protein is activated as it binds GTP.
4. Activated G protein activates the effector enzyme adenylate cyclase.
5. Adenylate cyclase generates cAMP (2nd messenger) from ATP
6. cAMP activates protein kinases which catalyze cellular effects
*Textbook: pg. 604
Name each blood group, and the type of blood that can be received by each. Which of these blood groups is the universal donor and which is the universal recipient?
A: can receive A or O Blood
B: can receive B or O blood
AB: can receive A, B, AB or O blood (universal recipient)
O: can receive O blood (universal donor)
Name the 3 major waves seen on an ECG and the event that occurs at each. Additionally, name the event we are unable to see on an ECG and where it is located.
P wave: atrial depolarization of the SA node (atrial contraction)
QRS complex: ventricular depolarization (ventricle contraction)
T wave: ventricular repolarization (ventricles return to resting state)
Behind QRS complex: atrial repolarization (atria return to resting state)
In which blood vessel is systemic blood pressure the highest?
In the aorta.
Highest to lowest:
Aorta -> Arteries -> Arterioles -> Capillaries -> Venules -> Veins -> Vena Cavae
List the steps of steroid hormone action.
1. Steroid hormone diffuses through plasma membrane into its target cells.
2. Bind to & activate intracellular receptors.
3. The activated hormone-receptor complex travels to the nuclear chromatin.
4. Complex binds to a specific region of DNA & "turns on" the gene (prompts the transcription of DNA to produce mRNA)
5. mRNA is translated into specific proteins, bringing about a cellular effect
*Textbook: pg. 606
Describe the 4 steps of hemostasis.
1. Vascular spasms: immediate vasoconstriction in response to injury
2. Platelet plug formation: platelets aggregate & form temporary plug to stop the flow of blood out of the vessel
3. Coagulation: blood clotting; reinforces platelet plug with fibrin threads
4. Clot retraction & repair: clot is compacted & fibrinolysis removes the unneeded clot once healing has occurred
*Textbook: pg. 658-660
List the pathway of the blood through the heart, beginning with the vena cava and ending with the arteries of systemic circulation.
Vena cava -> right atrium -> tricuspid valve -> right ventricle -> pulmonary SL valve -> pulmonary trunk -> pulmonary arteries -> lungs -> pulmonary veins -> left atrium -> bicuspid valve -> left ventricle -> aortic SL valve -> aorta -> arteries of systemic circulation
Name the main factors that influence blood pressure.
1. Cardiac Output (CO)
2. Peripheral Resistance (PR)
3. Blood Volume (BV)