Exam 5, Chapters 16-19

Which hormones are released by the anterior pituitary gland and what are their actions?

• adrenocoricotropic hormone (ACTH) - release cortisol

• follicle-stimulating hormone (FSH) - stimulates follicular cells to secrete estrogen (F); stimulates production of sperm cells (M)

• growth hormone (GH) - promotes growth of long bones

• luteinizing hormone (LH) - triggers ovulation

• prolactin (PRL) - milk production after birth

• thyroid-stimulating hormone (TSH) - controls secretion of hormones from thyroid gland

What are the functions of parathyroid glands and where are they located?

• posterior surface of thyroid gland

• secrete parathyroid hormone

• released when blood calcium levels too slow… need calcium balance

1. increase release of calcium ions from bone by stimulating osteoclasts

2. increasing absorption of dietary calcium ions by small intestine

3. increasing reabsorption of calcium ions from fluid in kidneys

Explain the concerns surrounding Rh(-) mothers who are pregnant with Rh(+) fetuses.

• hemolytic disease caused by maternal antibodies attacking fetal red blood cells

Know the characteristics of erythrocytes (RBCs).

• biconcave discs

  • increased flexibility, easy flow

• lack nuclei, mitochondria

  • carry more oxygen

• transport oxygen

• hemopoiesis - producing formed elements

• fractionation - process of separating whole blood for clinical analysis into plasma & formed elements

• 38C (100.4F) is normal temperature

• high viscosity

• pH of 7.4

• 7% of body weight

• cannot divide

Which vitamins are required for RBC production?

• vitamin B12 - for DNA synthesis

• vitamin B6 - for hemoglobin synthesis

• amino acids - building blocks for globin

• iron - form heme of hemoglobin 

• folic acid - for DNA synthesis and cell division

Know the generalized functions of the following: neutrophils, eosinophils, basophils, lymphocytes, and monocytes.

1. neutrophils - ~60%, fight bacterial infections

2. eosinophils - ~3%, defense against parasitic worm infestations & allergic reactions

3. basophils - <1% , release chemicals helping with inflammation

4. lymphocytes - ~30%, immunity

   1. T cells - attack foreign cells

   2. B cells - produce antibodies

5. monocytes - ~6%, largest; phagocytize bacteria, dead cells, and other debris

Describe the basic steps of hemostasis (blood clotting).

1. Vascular Phase - vascular spasm, blood vessel vasoconctricts

2. Platelet Phase - platelet adhesion (attachment) & platelet aggregation (stick together)

3. Coagulation Phase - blood clotting (coagulation)

Know the composition of plasma including the plasma proteins.

• water (~90%)

• plasma proteins (~9%)

  • albumin - transport substances (fatty acids, thyroid hormones, steroid hormones)

  • globulin - antibodies, aka immunoglobulins; transport globulins

  • fibrinogen - form clots and produce long, insoluble strands of fibrin

  • transferrin

• small solutes (~1%)

  • nutrients (glucose, amino acidsm nitrogenous wastes, ions, dissolved gases of oxygen and carbon dioxide)

What is the equation for stroke volume?

• SV = EDV - ESV

  • SV = stroke volume

  • EDV = end diastolic volume, filling/relaxing

  • ESV = end systolic volume, contracting

Where can a pulse be located?

brachial, carotid, radial, femoral, dorsalis pedis, posterior tibial arteries

Why are the action potential and contractile phase longer in cardiac muscle than skeletal muscle? How does cardiac muscle compare to skeletal and smooth muscles?

allow blood ejection from heart

1. Skeletal - striated, voluntary, attached to bones

2. Cardiac - striated, involuntary, heart

3. Smooth - non-striated, involuntary, walls of organs

Know the 5 factors that increase blood pressure.

1. increased heart rate

2. increased stroke volume

3. increase blood viscosity

4. increased peripheral resistance

5. increased blood volume

Label blood flow and know the steps.

Superior and Inferior vena cavae and Coronary sinus (veins) → right atrium (receiving chamber) → tricuspid valve (AV valve) → right ventricle (pumping chamber) → pulmonary valve (semilunar valve) → pulmonary trunk (artery) branches into the right and left pulmonary arteries (artery) → gas exchange at lungs (blood loses CO2 & gains O2) → right and left pulmonary veins (veins) → left atrium (receiving chamber) → bicuspid valve (AV valve) → left ventricle (pumping chamber) → aortic valve (semilunar valve) → aorta branches into systemic arteries (arteries) → gas exchange at the tisses (blood loses O2 & gains CO2)

Label heart.

What are the basic structures of steroid hormones and non-steroid hormones?

• steroid hormones - derived from cholesterol, with core hydrocarbon rings

  • hydrophobic & interact with plasma membrane or intracellular receptors

  • sex hormones, adrenal cortex hormones

• non-steroid hormones - amino acid-based, water-soluble, use second messengers

  • amines, proteins, peptides, glycoproteins

What substance is needed to make steroids?

cholesterol

Name the hormones which are derived by cholesterol.

cortisol, aldosterone, estrone, progesterone, testosterone

Describe the steps of the hypothalamus in controlling endocrine functions.

• hypothalamus → anterior pituitary gland → peripheral endocrine gland → target cells → action

1. production of ADH and oxytocin

2. secretion of regulatory hormones to control activity of anterior lobe of pituitary gland

3. control of sympathetic output to adrenal medullae

What are the functions of the two hormones of the posterior pituitary hormones?

• antidiuretic hormone (ADH)  - causes kidneys to reduce water excretion

• oxytocin (OT) - milk ejection

List the endocrine glands and their basic functions.

• hypothalamus - links nervous & endocrine systems

• pituitary gland - produce hormones, release ADH & oxytocin

• thyroid gland - produce T3 & T4, regulate metabolism

• thymus - help make T-lymphocites

• parathyroid glands - increase blood calcium levels

• pineal gland - 

• adrenal glands - fight or flight response, respond to stress

• pancreas - regulate blood glucose levels

• testes - produce testosterone, control sperm production

• ovaries - produce estrogen and progesterone, regular menstrual cycle & pregnancy

Describe how the three calcium controlling hormones work.

1. Parathyroid Hormone (PTH) - stimulus for release is decrease in plasma Ca²⁺ monitored by Ca²⁺-sensing receptor

   1. raises plasma Ca²⁺ in three ways

      1. mobilizes calcium from bone

      2. enhances renal reabsorption of calcium

      3. indirectly increases intestinal absorption of Ca²⁺

2. Calcitrol - aka vitamin D₃

   1. primary hormone responsible for enhancing Ca²⁺ uptake

   2. facilitates renal absorption of Ca²⁺ out of bone

   3. production is regulated by action of PTH

3. Calcitonin - released when plasma Ca²⁺ increases

   1. decreases bone resorption

   2. increases renal calcium excretion

Describe the important functions of calcium.

• calcified matrix of bone and teeth

• neurotransmitter release at synapse

• role in myocardial and smooth muscle contraction

• cofactor in coagulation cascade

• “cement” for tight junctions

• influences excitability of neurons

• muscle contraction

• signal in second messenger pathaways

Know the hormones of the adrenal medulla and the cortex and describe their functions.

• adrenal medulla:

  • epinephrine (E) & nonrepinephrine (NE)

    • fight or flight

    • blood glucose increases

    • blood glycerol and fatty acids increase

    • heart rate increases

    • blood pressure rises

    • breathing rate increases

    • air passages dilate

    • blood flow redistributes

• adrenal cortex: 

1. cortisol - stress hormone, stimulates fluconeogenesis, fat & protein breakdown, inhibits inflammatory response

2. aldosterone - increase reabsorption of sodium ions & water, secretion of potassium & hydrogen ions, maintaining blood pressure & acid-base homeostasis

3. androgens - sex hormones affecting reproductive organs that trigger development of male physical characteristics 

How does cortisol affect the immune system?

• acts as anti-inflammatory agent by decreasing levels of leukocytes

• suppress immune response

Describe how the pancreas can function as an endocrine and exocrine gland.

• has two major types of secretory tissue

  • two groups of cells within pancreas

1. endocrine cells - islet cells

   1. secrete glucagon (alpha), insulin (beta), somatostatin (delta)

2. exocrine cells - acinar cells

   1. digestive enzymes

Know the functions of blood.

1. regulate pH & ions

2. restrict fluid losses at injury sites

3. defense against toxins & pathogens

4. transport materials to & from cells

   1. oxygen & carbon dioxide, nutrients, hormones, waste products, immune system components

5. exchange gases

6. distribute solutes

7. maintain body temperature

8. stabilize blood pressure

Know the 3 components that make up blood.

1. plasma - ~55%

   1. water, plasma proteins, small solutes

2. buffy coat - <1%

   1. white blood cells, platelets

3. RBC - ~44%

   1. erythrocytes

Define hemoglobin and understand its functions.

• protein molecule consisting of four polypeptide subunits of iron ions

• heme binds to oxygen where oxygen levels are high forming oxyhemoglobin

• when oxygen levels are low, hemoglobin releases oxygen to become deoxyhemoglobin

Understand why Type O blood individuals are universal donors and why Type AB blood individuals are universal recipients.

• Type O = no antigens, donor

• Type AB = no antibodies, recipients

• antibodies attack antigens

Name 2 substances required for blood coagulation.

calcium, vitamin K

What is the function of auricles?

appendages that increase atrial volume

What is the function of papillary muscles? What are the chordae tendineae? What is their function?

• papillary muscles attach to chordae tendineae

• prevent cusps from ballooning back to atria

What three veins empty into the right atrium? What veins empty into the left atrium?

• right atrium - superior vena cava, inferior vena cava, coronary sinus

• left atrium - pulmonary veins

Know the location of AV valves.

• tricuspid valve - between right atrium and right ventricle

• bicuspid - between left atrium and left ventricle

Know the flow of blood through the pulmonary and systemic circuit.

• right atrium → right ventricle → pulmonary trunk → lungs → left atrium → left ventricle → aorta → body → right atrium

  • right side receives oxygen-poor blood from tissues

    • pumps to lungs to get rid of CO2, pick up O2, via pulmonary circuit

    • left atrium receives blood from pulmonary circuit

    • right ventricle pumps blood through pulmonary circuit

  • left side receives oxygenated blood from lungs

    • pumps to body tissues via systemic circuit

    • right atrium receives blood returning from systemic circuit

    • left ventricle pumps blood through systemic circuit

What is the function of the coronary sinus?

where heart’s veins empty which then drains into right atrium

Define myocardial infarction.

• heart attack

• occurs when plaques in coronary arteries rupture & clot forms that obstructs blood flow to myocardium

What is the function of intercalated discs?

anchor cardiac cells

What are the 3 parts of the cardiac action potential? What ions are involved?

1. depolarization - Na⁺ in

2. plateau phase - Ca²⁺ out

3. repolarization - K⁺ out

Describe what occurs during the phases of an ECG: P wave, QRS complex, T wave.

• P wave - depolarization SA node → atria

• QRS complex - ventricular depolarization & atrial repolarization

• T wave - ventricular repolarization

Know the “sounds” of the heart, 1st and 2nd. LUB-DUP

• 1st - lub; AV valves close, beginning of systole

• 2nd - dup; SL valves close, beginning of ventricular diastole

Define CO, SV, HR. How are they connected?

• CO = HR x SV

  • CO = cardiac output, normal = 5.25 L/min

  • HR = heart rate, number of beats per minute

  • SV = stroke volume, volume of blood pumped out by one ventricle with each beat

Define preload, contractibility, afterload.

• preload - degree of stretch of cardiac muscle cells before they contract

• contractibility - contractile strength at given muscle length, independent of muscle stretch & EDV

• afterload - pressure ventricles must overcome to eject blood

How does epinephrine, norepinephrine, ANG II, ADH, ANP (lowers BP), and aldosterone affect blood pressure?

• epinephrine - increase BP

• norepinephrine - increase BP

• ANG II - increase BP, vasoconstriction

• ADH - increase VP, water retention

• aldosterone - increase BP, retain sodium

• ANP - decrease BP, vasodilation

What are the functions of angiotensin II?

• increase thirst

• sodium ion retention

• secretion of aldosterone

• increase blood volume

What are the 3 mechanisms used to move blood through the veins?

1. skeletal muscle pump

2. respiratory pump

3. venous valves