module 3 reds

Question 1

features of the nasal cavity

Answer 1

large sa, hairy lining, moist surfaces (red evaporation)

Question 2

features of the trachea

Answer 2

rings of cartilage, lined with ciliated epithelium and goblet cells

Question 3

features of the bronchus

Answer 3

smaller trachea

Question 4

features of the bronchioles

Answer 4

no cartilage, smooth muscle in walls to allow constriction and dilation, thin layer of flattened epithelium

Question 5

features of alveoli

Answer 5

thin flattened epithelium cells, collagen, elastin,

Question 6

adaptations of alveoli

Answer 6

large sa, thin walls, good blood supply, good ventilation

Question 7

inspiration

Answer 7

internal intercostal relax, ribs move up and out

Question 8

expiration

Answer 8

external intercostal relax, ribs move down and in

Question 9

forcible expiration

Answer 9

internal intercostal contract, pulling ribs down and in hard. abdominal muscles contract, forcing diaphragm up to increase pressure in lungs

Question 10

what happens at arteriole end of capillary

Answer 10

-plasma proteins give capillary low oncotic pressure
-high hydrostatic pressure (from heart pumping blood) forces fluid out
-fluid between cells = tissue fluid

Question 11

what happens at venous end

Answer 11

-hydrostatic pressure falls below oncotic pressure
-water moves in via osmosis

Question 12

composition of tissue fluid

Answer 12

same as blood minus red blood cells and plasma proteins

Question 13

composition of lymph

Answer 13

same as tissue fluid but fewer nutrients and oxygen, and fatty acids

Question 14

what is lymph

Answer 14

remaining tissue fluid drains into lymph capillaries

Question 15

what are lymph nodes

Answer 15

intercept bacteria. lymphocytes build up to produce antibodies

Question 16

positive cooperativity

Answer 16

haemoglobin changes shape with oxygen binding

Question 17

bohr effect

Answer 17

high pco2, more o2 released

Question 18

transport of co2 (%)

Answer 18

5% in plasma
10-20% in amino groups in haem (carbaminohaemoglobin)
75-85% as hco3-

Question 19

how is carbon converted to hco3-

Answer 19

co2 + h2o -> h2co3 -> h+ + hco3-
carbon dioxide + water -> carbonic acid -> hydrogen ions + hydrogen carbonate ions
catalysed by carbonic anhydrase in rbcs

Question 20

chloride shift

Answer 20

hco3- moves out, cl- moves in to maintain charge

Question 21

flow of blood through right side of heart

Answer 21

deox blood enters through vena cava from body, leaves through pul artery

Question 22

flow of blood through left side of heart

Answer 22

ox blood enters through pul vein from lungs, leaves through aorta to body

Question 23

what is the cardiac cycle

Answer 23

describes events in a single heartbeat

Question 24

what happens in diastole

Answer 24

relaxation, fill with blood, pressure increases but is at minimum in arteries

Question 25

what happens in systole

Answer 25

atria then ventricles contract. pressure increases dramatically, blood forced out. pressure in arteries at max

Question 26

what is the sino atrial node

Answer 26

pacemaker area which initiates beat, top of atrium, causes atrial contraction

Question 27

what is the atrioventricular node

Answer 27

picks up san wave, stimulates bundle of his

Question 28

what is the bundle of his

Answer 28

conducting tissues made of purkyne fibres (penetrate septum at top). splits into two branches and stims apex. ventricles contract