Bio 2252L Exam 1

Hypothalamus

regulates the release of hormones from the pituitary glands,
makes oxytocin, ADH

Anterior pituitary

makes prolactin, ACTH, TSH, growth hormone

Posterior pituitary

stores oxytocin, ADH

Pancreas

contains the islets of Langerhans that produce insulin/glucagon

Adrenal cortex

makes aldosterone, cortiso

Adrenal medulla

makes epinephrine and norepinephrine

Thyroid gland

this organs follicular cells makes thyroxin (T3/T4), parafollicular
cells make calcitonin

Parathyroid gland

makes PTH

Pineal gland

makes melatonin

Testes

makes testosterone to stimulate sperm production

Ovaries

makes estrogen, progesterone prepare/maintain endometrium

RBC

transport oxygen

Eosinophils

Allergen removal, destroy parasites like worms

Basophils

Promote inflammation, histamines

Monocytes

Macrophages active phagocytes

Lymphocytes

Produce antibodies, attack viruses

Neutrophils

phagocytic removal of foreign material

Platelets

Clotting

Superior and inferior vena cava and coronary sinus to the right atrium ---______________valve----right ventricle ---
pulmonary valve--- pulmonary trunk ---- ____________ arteries ----- lungs to ---
Left pulmonary vein  left ______  bicuspid valve  left ___________ --- aortic valve ---aorta

Superior and inferior vena cava and coronary sinus → right atrium → tricuspid valve → right ventricle → pulmonary valve → pulmonary trunk → pulmonary arteries → lungs → pulmonary veins → left atrium → bicuspid (mitral) valve → left ventricle → aortic valve → aorta.

The coronary artery feeds into the _________ artery and the ______________ artery.
The pulmonary ___________ carry oxygenated blood and the pulmonary ___________ carry deoxygenated blood.

The coronary artery feeds into the anterior interventricular artery (LAD) and the circumflex artery. The pulmonary veins carry oxygenated blood.The pulmonary arteries carry deoxygenated blood.

Trace the path of blood through the heart by placing the steps in the proper order.

1. Blood enters right atrium from the superior and inferior vena cava and coronary sinus.

2. Blood in right atrium flows through the tricuspid valve (right AV valve) into the right ventricle.

3. Blood flows through the pulmonary valve into pulmonary trunk.

4. Blood is distributed by right and left pulmonary arteries to the lungs, where it unloads CO2 and loads Oxygen.

5. Blood returns from lungs from the pulmonary veins to left atrium.

6. Blood in left atrium flows through the mitral valve (left AV valve) into left ventricle.

7. Blood flows through aortic valve into ascending aorta.

The flow of blood through the heart and pulmonary circulation occurs in which sequence?

1. ) Left atrium

2. Tricuspid valve

3. ) Mitral valve

4. ) Left ventricle

5. Aortic valve

6. Right ventricle

7. ) Pulmonary valve

8. ) Right atrium

9. ) Pulmonary artery

10. Lungs

11. Pulmonary veins

12. Aorta

8, 2, 6, 7, 9, 10, 11, 1, 3, 4, 5, 12

What is the function of the hypothalamus in the endocrine system?

Regulates release of hormones from the pituitary gland; also produces oxytocin and ADH (stored in posterior pituitary).

What is the infundibulum of the hypothalamus?

The stalk that connects the hypothalamus to the pituitary gland (hypophysis)

What are the two lobes of the pituitary gland and how do they connect to the hypothalamus?

Anterior pituitary (adenohypophysis) — connected via the hypophyseal portal system.

Posterior pituitary (neurohypophysis) — connected via the hypothalamic-hypophyseal tract.

List the 4 tropic hormones of the anterior pituitary and their targets.

FSH — stimulates sperm/ova development

LH — triggers *ex hormone secretion

ACTH — stimulates adrenal cortex

TSH — stimulates thyroid hormone activity

What two non-tropic hormones does the anterior pituitary secrete?

Growth Hormone (GH) — general metabolic hormone affecting body size

Prolactin (PRL) — stimulates breast development and lactation

What hormones does the posterior pituitary RELEASE (not make)?

Oxytocin — stimulates uterine contractions and milk ejection

ADH (antidiuretic hormone) — causes kidneys to reabsorb water

Describe the thyroid gland anatomy

Two-lobed organ in the throat above the larynx; lobes connected by the isthmus.

What hormones does the thyroid gland produce and what do they do?

T3/T4 (thyroid hormones) — control metabolic rate and cellular oxidation

Calcitonin — decreases blood Ca²■ by stimulating calcium deposit in bones

Where are the parathyroid glands located and what do they secrete?

Embedded on the posterior side of the thyroid gland (4 small oval glands).

Secrete PTH (parathyroid hormone) — raises blood Ca²■ by breaking down calcium from bone.

What does the adrenal medulla secrete and what controls it?

Epinephrine and Norepinephrine — released during short-term stress.

Controlled by the sympathetic nervous system.

Name the 3 groups of corticosteroids from the adrenal cortex.

Mineralocorticoids — regulate water/sodium balance (e.g., aldosterone)

Glucocorticoids — stress resistors, raise blood glucose (e.g., cortisol)

Gonadocorticoids (Androgens) — precursors to sex hormones

What are the three regions of the pancreas? What hormones does it produce?

Regions: Head, Body, Tail

Insulin — lowers blood glucose (transports glucose into cells)

Glucagon — raises blood glucose (liver breaks down glycogen)

What hormones do the ovaries and testes produce?

Ovaries: Estrogen (secondary sex characteristics, uterine lining) + Progesterone (prep breast tissue,uterus)

Testes: Testosterone (secondary sex characteristics, sperm production)

What does the thymus produce and what is its role?

Thymosin and Thymopoietin — direct T-cell development.

Large and active in childhood; atrophies in adulthood.

What does the pineal gland secrete and what is its function?

Melatonin — regulates circadian rhythms/biological clock.

Describe the thyroid follicle histology — what are the three cell types and what does each do?

Thyroid follicle — entire circular structure filled with colloid

Follicular cells — line the follicle; secrete T3/T4 (thyroid hormones)

Parafollicular cells (C cells) — between follicles; secrete calcitonin

Describe the pancreas histology — identify the two structures and their functions.

Pancreatic acini (acinar cells) — exocrine; produce digestive enzymes

Pancreatic islets (Islets of Langerhans) — endocrine; contain alpha cells (glucagon) and beta cells (insulin)

What is the difference between an endocrine and exocrine gland?

Endocrine — ductless; secretes hormones directly into bloodstream

Exocrine — has ducts; secretes products to a surface (e.g., sweat glands, salivary gland

What are the two main components of blood and their approximate percentages?

Plasma — 55% (90% water; contains albumin, fibrinogen, globulins, hormones)

Formed elements — 45% (RBCs, WBCs, platelets)

Describe erythrocytes (RBCs): function, appearance, abundance.

Function: Transport O■ and CO■; aid blood pH regulation

Appearance: Biconcave discs, no nucleus, orange-red (eosinophilic stain)

Size: ~7.5 µm; make up 99% of formed elements

Describe platelets: function, appearance, abundance.

Function: Hemostasis (blood clotting)

Appearance: Small, purple fragments of megakaryocytes (~2 µm)

Abundance: ~1% of formed elements

What is the general function and appearance of leukocytes (WBCs)?

Function: Protect body from pathogens, fight infection, remove dead cells

Appearance: Blue-purple nuclei (basophilic staining)

Size: 7–21 µm; less than 1% of formed elements

Describe neutrophils: function, appearance, abundance.

Function: Phagocytize bacteria and damaged cells (first responders)

Appearance: Multi-lobed nucleus (2–5 lobes); light lavender granules

Abundance: 50–70% of leukocytes

Describe eosinophils: function, appearance, abundance.

Function: Fight parasites; neutralize histamines; phagocytic

Appearance: Bi-lobed bluish nucleus; ORANGE-RED cytoplasmic granules

Abundance: 1–4% of leukocytes

Describe basophils: function, appearance, abundance.

Function: Release histamine and heparin; inflammatory response

Appearance: Bi-lobed nucleus often hidden by very dark BLUE granules

Abundance: 0.5–1% of leukocytes

Describe monocytes: function, appearance, abundance.

Function: Circulate and become macrophages (large phagocytic cells)

Appearance: Horseshoe-shaped blue/purple nucleus; large (2–3× RBC)

Abundance: 2–8% of leukocytes

Describe lymphocytes: function, appearance, abundance.

Function: Adaptive immune response (produce antibodies, attack viruses)

Appearance: Large blue/purple nucleus with halo of pale blue cytoplasm

Abundance: 20–40% of leukocytes

Memory trick: What is the order of WBCs from most to least abundant?

Never Let Monkeys Eat Bananas

Neutrophils → Lymphocytes → Monocytes → Eosinophils → Basophils

(50–70%, 20–40%, 2–8%, 1–4%, 0.5–1%)

What is hematocrit and what are normal values?

Hematocrit = percentage of blood volume that is RBCs (packed cell volume).

Normal: ~42–52% for males, ~37–47% for females.

Procedure: Spin blood in heparinized capillary tube in centrifuge.

What is anemia vs. polycythemia in terms of hematocrit?

Anemia — abnormally LOW hematocrit; not enough RBCs to carry O■

Polycythemia — abnormally HIGH hematocrit; too many RBCs, blood too thick

Explain ABO blood typing — what antigens/antibodies does each blood type have?

Type A: A antigens, anti-B antibodies

Type B: B antigens, anti-A antibodies

Type AB: A and B antigens, NO antibodies (universal recipient)

Type O: NO antigens, anti-A and anti-B antibodies (universal donor)

What are agglutinogens and agglutinins?

Agglutinogens = antigens on the surface of RBCs that can cause clumping

Agglutinins = antibodies in plasma that react against foreign agglutinogens

What is the Rh factor and what does Rh+ vs. Rh− mean?

Rh factor = antigen (D antigen) on RBC surface.

Rh+ — has the Rh antigen

Rh− — lacks the Rh antigen; can develop anti-Rh antibodies after exposure to Rh+ blood

Where is the heart located?

In the mediastinum, superior to the diaphragm, centered slightly left of the midsternal line in the cardiac notch of the left lung.

What is the fibrous pericardium?

Outer connective tissue sac that encloses and protects the heart; anchors it to surrounding structures.

What is the pericardial cavity?

Space between the visceral and parietal layers of the serous pericardium; contains pericardial fluid to reduce friction.

Name the 4 layers of the heart wall from outside to inside.

1. Fibrous pericardium (outermost)

2. Epicardium (visceral serous pericardium) — connective tissue with vessels/nerves

3. Myocardium — cardiac muscle (contractile tissue)

4. Endocardium — epithelial lining of chambers and valves

What is the apex vs. the base of the heart?

Apex — pointed inferior tip of the heart (points down and left)

Base — broad flat superior portion (where great vessels attach)

What is the coronary sulcus?

Groove on the external surface of the heart that separates the atria from the ventricles; contains coronary vessels.

Differentiate anterior vs. posterior interventricular sulcus.

Anterior interventricular sulcus — groove on front of heart marking the boundary between right and left ventricles

Posterior interventricular sulcus — groove on back of heart; same function

What is the ligamentum arteriosum?

Fibrous remnant of the ductus arteriosus (fetal vessel connecting pulmonary trunk to aorta); non-functional after birth.

What is the fossa ovalis?

Oval depression in the interatrial septum; remnant of the foramen ovale (fetal opening between atria).

What are pectinate muscles vs. trabeculae carneae?

Pectinate muscles — ridged muscle in the right atrium and auricles

Trabeculae carneae — irregular ridges of muscle lining the ventricles

Name the 4 heart valves and what backflow each prevents.

Tricuspid (right AV) — prevents backflow into right atrium

Pulmonary semilunar — prevents backflow into right ventricle

Bicuspid/Mitral (left AV) — prevents backflow into left atrium

Aortic semilunar — prevents backflow into left ventricle

What are chordae tendineae and papillary muscles?

Papillary muscles — conical muscles projecting from ventricular walls

Chordae tendineae — 'heart strings' anchoring AV valve cusps to papillary muscles; prevent valve inversion during contraction

What is the interventricular septum?

Muscular wall separating the right and left ventricles.

Trace the complete path of blood through the heart.

Superior/inferior vena cava & coronary sinus → Right atrium → Tricuspid valve → Right ventricle → Pulmonary semilunar valve → Pulmonary trunk → Right & left pulmonary arteries → Lungs → Pulmonary veins → Left atrium → Bicuspid valve → Left ventricle → Aortic semilunar valve → Aorta → Body

Which pulmonary vessels carry oxygenated vs. deoxygenated blood?

Pulmonary ARTERIES — carry deoxygenated blood (toward lungs)

Pulmonary VEINS — carry oxygenated blood (from lungs to left atrium)

What is the coronary circulation?

Coronary arteries branch from the aorta to supply oxygenated blood to the heart muscle (when heart is relaxed/diastole).

Cardiac veins drain deoxygenated blood back to the right atrium via the coronary sinus.

Name the major coronary arteries and their branches.

Left coronary artery → Circumflex artery + Anterior interventricular artery (LAD)

Right coronary artery → Marginal artery + Posterior interventricular artery

Name the cardiac veins.

Great cardiac vein, Middle cardiac vein, Small cardiac vein, Anterior cardiac vein → drain into coronary sinus → right atrium

Describe cardiac muscle histology — what structures are unique to it?

Striations (actin/myosin), centrally placed nucleus, intercalated discs (connect cells for synchronized contraction), sarcolemma.

Intercalated discs contain gap junctions — allow electrical signals to spread rapidly.

What is the difference between pulmonary and systemic circuits?

Pulmonary circuit — right heart pumps deoxygenated blood to lungs for gas exchange; returns oxygenated

blood to left heart.

Systemic circuit — left heart pumps oxygenated blood to the body; returns deoxygenated blood to right heart.