Digestive system

Question 1

types of feeding methods

Answer 1

filter/suspension feeders 
detritivores (deposit feeders)
fluid feeders 
carnivores 
herbivores 
omnivores 
symbiotic-autotroph bearers (carry other organisms but produce nutrients for them)

Question 2

size and filter/suspension feeders

Answer 2

e. g. whales/crinoid

v. big or v.small

Question 3

example of a symbiotic-autotroph bearer

Answer 3

tube worm

Question 4

two mechanism which link functions of digestive tract with outside world

Answer 4

hunger mechanism

thirst mechanism

Question 5

Hunger mechanism hormones

Answer 5

grelin - feel hungry (produced by stomach)

leptin - feel satiated (produced by adipose cells)

Question 6

leptin resistance

Answer 6

leads to obesity

no longer feel hungry

Question 7

order of choice of source of energy in body (human)

Answer 7

1. carbohydrate
2. fats
3. protein

Question 8

why does energy production decrease with different sources of energy than carbohydrate?

Answer 8

fats (glycerol & fatty acids) and proteins (amino acids) come in on cycle later on than with carbohydrate and therefore potential ATP production from missed steps is lost

Question 9

types of extracellular digestion (evolution)

Answer 9

1. gastrovascular cavity

2. set of complete tubes

Question 10

motility - muscles

Answer 10

smooth muscle under autonomic control 
BOTH tonic (low tone contraction)  and phasic (periodical contractions triggered)

Question 11

general aspects of digestion

Answer 11

motility
secretion
digestion
absorption

Question 12

control of digestive system

Answer 12

Autonomous smooth muscle
Local sensory receptors
Intrinsic nerves
Extrinsic nerves (sympathetic & parasympathetic)
GIT hormones

Question 13

4 basic layers of tissue in digestive tract

Answer 13

outermost layer - seroza

conducting & contracting - smooth muscle layer +enteric nervous system

connective - submucosa

covering (epithelial tissue) - mucosa

lumen

Question 14

enteric nervous system

Answer 14

almost a completely separate nervous system with digestive system

Question 15

glands in the digestive tract

Answer 15

liver
pancreas
salivary

Question 16

what is the mucosa layer made up of?

Answer 16

1. epithelium
2. lamina propria (lymphoid tissue & mucus producing glands
3. muscularis mucosi (first layer of folding)

Question 17

what is the mucosa layer made up of?

Answer 17

1. epithelium
2. lamina propria (lymphoid tissue & mucus producing glands
3. muscularis mucosi (first layer of folding) - capillaries and ends of lymphatic system

Question 18

what does the seroza do?

Answer 18

full support of digestive tract - keeps it in place (epithelium + connective)

Question 19

what does the submucosa constain?

Answer 19

glands & blood vessels - arterioles and venuoles

Question 20

what does the mucosa do?

Answer 20

secrete some of digestive enzymes (hold in brush border - microvilli)

Question 21

interesting difference with snail

Answer 21

radula - grind food with mouth & suck in

Question 22

spiral valves - where found & what do?

Answer 22

sharks

short digestive tract - used to slow passage of food

Question 23

cloaca as oppose to anus

Answer 23

combined urinary and digestive tract exit

Question 24

crop - what is it? & who has it?

Answer 24

gravel in it (birds), grind, pre-stomach

found in birds & insects

Question 25

mouthpart types - invertebrate

Answer 25

sponge (and suck) - e.g. flies
proboscis - suck up food - e.g. butterflies
mandibles - e.g. tiger beetle

Question 26

how to insects intially taken up food?

Answer 26

sucking

Question 27

mouthparts - vertebrate adaptations

Answer 27

chizel-like teeth - rodents
fangs - venom channel in tooth
sharks - many rows of teeth
cats& dogs drink by lapping

Question 28

what is different about herbivores teeth?

Answer 28

teeth keep growing

Question 29

insect midgut

Answer 29

mesenteron

Question 30

what is the peritrophic (matrix) membrane?

Answer 30

Insect midgut

internal body-organ tissue
made of chitin
floats above aborption layer
carries enzymes

Question 31

ruminant stomach

Answer 31

abommasum - similar to stomach in humans

Question 32

names of four chambers in ruminant midgut

Answer 32

rumen
reticulum
omasum
abomasum

Question 33

limitation to ruminant digestion environments

Answer 33

fibrous material can slow down digestion and lead to starvation

Question 34

birds digestion order

Answer 34

glandular stomach - enzymes secreted

gizzard - grit & grinding

Question 35

caecum with diet

Answer 35

smaller if eat more meat (carnivorous)

Question 36

where is the fat body found?

Answer 36

insects - storage organ/lymphatic system/endocrine system/immune/excretion

Question 37

what is a hepatopancreas?

Answer 37

does same job as liver and pancreas but one organ

- arthropods, molluscs, fish