Biology Ch. 4 Flashcards
Pathway of Air
Nose/mouth
Pharynx
Larynx
Trachea
Bronchi
Bronchioles
Alveoli
In Alveoli, O2 and CO2 are passed by:
Simple Diffusion
Respiratory Control
Medulla oblongata (medulla)
Chemoreceptors measure H+ concentration.
Peripheral chemoreceptors also monitor in the carotid arteries and aorta.
Respiratory System:
Goblet cells
Basal cells
Cilia cells
G: secrete mucus
B: produce new cells
C: sweep debris trapped by mucus.
Most efficient respiratory organ:
Gills in fish via countercurrent exchange
Main buffer molecule in blood
Bicarbonate
Catalyzed by carbonic anhydrase.
Also transports CO2 in blood.
Shifts in the O2-Hemoglobin Association Curve
Left: oxygen held more tightly.
Right: oxygen held loosely; physiological conditions where tissues need more oxygen.
Increase in CO2, Acid, 2,3DPG, Exercise, and Temp cause right shifts.
Systole vs. Diastole
S: heart contracts.
D: heart relaxes.
Cardiac Output
Stroke Volume x Heart Rate
Arteries
Arterioles
Capillaries
Venules
Veins
Arteries: thick walls, lots of smooth muscle, elastic.
Arterioles: smooth muscle, major determinant of BP.
Capillaries: single layer of endothelial cells, play role in Temp regulation and BP.
Venules: smallest vein components, very thin and porous.
Veins: Same layers as arteries but much thinner walls; have valves to prevent backflow.
Precapillary Sphincter
Regulates passage of blood into capillaries based on need.
Ex: less blood flow to skeletal muscles when relaxing.
Ductus Venosus
Foramen Ovale
Ductus Arteriousus
DV: bypasses liver.
FO: hole between atria to bypass lungs.
DA: another opportunity to bypass lungs, connects pulmonary artery to aorta.
Universal Donor/Recipient
Donor: O-
Recipient: AB+
Clotting Cascade
Injury that exposes broken BV wall.
Collagen attracts platelets (platelet plug).
Platelets trigger enzyme cascade that converts prothrombin to thrombin (+FB).
Thrombin converts fibrinogen to fibrin, which reinforces the platelet plug to form a clot.
Central Lymphoid Tissue
Can replenish lymphocytes.
Thymus: T cell maturation.
Bone marrow: produces lymphocytes.
Peripheral Lymphoid Tissues
Can’t replenish lymphocytes.
Lymph Nodes: contain leukocytes that filter lymph and initiate immune response.
Spleen: filters blood.
Adenoids: inspect food and air for pathogens.
Appendix: destroys bacteria before they breach intestinal wall.
Peyer’s Patches: aggregates of lymphoid tissue in the ileum.
Right Lymphatic Duct
Thoracic Duct
RLD: drains upper right area into jugular vein.
TD: drains rest of body into subclavian vein.
Lacteals
Lymph capillaries in digestive system.
Absorb emulsified fats to break down and send into circulation.
Loop of Henle
Descending loop: permeable to water; water leaves which increases the solute concentration.
Ascending loop: impermeable to water; NaCl gets removed which decreases the solute concentration.
Aldosterone and ADH
Aldosterone: increases Na reabsorption from tubules into bloodstream. Water follows Na out and back into the blood.
ADH: increases collecting duct permeability to water; water is reabsorbed out of the kidney and back into the bloodstream; urine becomes more concentrated.
Types of Stomach Cells (5)
Mucus cells: produce mucus to protect stomach lining.
Chief cells: secrete pepsinogen.
Parietal cells: secrete HCl and Intrinsic Factor.
G Cells: produce gastrin which stimulates parietal cells.
ECL cells: stimulated by gastrin; produce histamine to stimulate parietal cells.
Pancreas (Digestive Functions)
Secretes bicarbonate to neutralize acid.
Proteases: trypsin, chymotrypsin.
Secretes amylase, lipase, and nuclease.
Microbiome
Assist in digestion, immunity, and vitamin synthesis and absorption.
Extended use of ABs can cause vitamin deficiencies.
Gastrin
Stimulates secretion of HCl; triggered by food.
Secretin
Secreted by duodenum.
Triggered by presence of acid.
Signals pancreas to release bicarbonate.
Cholecystokinin (CCK)
Stimulates gall bladder to release bile and pancreas to release enzymes.
Slows gastric motility/emptying.
