Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

bio > digestion > Flashcards

digestion Flashcards

You may prefer our related Brainscape-certified flashcards:
Biology 101 flashcards
1
Q

define ingestion

A

the taking of substance, eg. food and drink, into the body though the mouth

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

define mechanical digestion

A

the breakdown of food into smaller pieces without chemical change to the food molecules

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

define chemical digestion

A

the breakdown of large, insoluble molecules into small soluble molecules

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

define absorption

A

the movement of small food molecules and ions through the wall of the intestine into the blood

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

define assimilation

A

the movement of digested food molecules into the cells of the body where they are used, becoming part of the cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

define egestion

A

the passing out of food that has not been digested or absorbed, as faeces, through the anus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

cholera is a disease caused by ___

A

bacterium

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

diarrhoea is treated using ___

A

oral rehydration therapy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

what does cholera bacterium do

A

produces a toxin that causes secretion of chloride ions into the small intestine -> reduces water potential in small intestine

  • > causing osmotic movement of water into the gut, causing diarrhoea
  • > dehydration and loss of salts from blood
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

amylase function

A

secreted by alimentary canal and breaks down starch into maltose

• maltose is broken down by maltase to glucose on the membranes of the epithelium lining the small intestine

breaks down large INSOLUBLE STARCH molecules to smaller more SOLUBLE disaccharide maltose

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

protease function

A

breaks down protein to amino acids

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

lipase function

A

breaks down fats to fatty acids and glycerol

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

(brief) what are the functions of HCl in gastric juice

A

low pH

  • denatures enzymes in harmful microorganisms in food
  • gives optimum pH for pepsin activity
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

(brief) role of bile

A
  • neutralises the acidic mixture of food and gastric juices entering the duodenum from the stomach, to provide a suitable pH for enzyme action
  • emulsifies fats to increase the surface area for the chemical digestion of fat to fatty acids and glycerol by lipase
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

water is absorbed in the ___ and the ____ but most of the absorption of water happens in the ______

A

water is absorbed in the small intestine and the colon but most of the absorption of water happens in the small intestine

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

the alimentary canal is ———-

A

a long tube running through the body from the mouth to the anus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

(role in digestive system) mouth

A

food is mixed with saliva and chewed to break it into smaller pieces which are easier to swallow and digest

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

(role in digestive system) liver

A

a large, important gland with many different jobs

it makes bile to emulsify fats so that they can mix with the digestive juices in the small intestine

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

(role in digestive system) gall bladder

A

stores bile made by the liver

when the fat is eaten, the bile is emptied into the duodenum

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

(role in digestive system) duodenum

A

first part of the small intestine

bile and juice from the pancreas are added to the food in the duodenum

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

(role in digestive system) large intestine (colon)

A

absorbs water from the chyme into the blood, leaving solid waste called faeces
absorbs bile salts from waste material
minerals are also absorbed

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

caecum

A

first large part of the large intestine

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

(role in digestive system) appendix

A

no part of digestion, little value to humans

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

rectum

A

last part of the large intestine

where the faeces (made up mainly of indigestible food) are stored before they are passed out through the anus (egestion)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

anus

A

the final sphincter

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

describe sphincters

A

Muscular walls thickened to form rings of muscle called sphincters

Can contract to close the tube and relax to open it

Sphincters at each end of the stomach can either hold food in the stomach or let it pass out

Main sphincters:
CS- cardiac spincter (start of stomach area)
PS- pyloric sphincter (end of stomach area)
ICV- ilio-caecal valve (around caecum)
AS- anal spincter (end of anus)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

name of the process of chewing

A

mastication

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

what does mechanical digestion do

A

increase the surface area of the food by breaking it into smaller pieces

• provides larger surface area for digestive enzymes where they can BREAK down COMPLEX food MOLECULES into SIMPLE ones (chemical)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

4 different types of teeth

A

incisors
canines
premolars & molars

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

incisors

A

chisel-shaped at the front of the mouth

used to cut pieces from food

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

canines

A

pointed teeth on both sides of the incisors

used for gripping and tearing

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

premolars and molars

A

flat-topped teeth in the cheeks (have points or cusps)

upper and lower cusps fit together

used for grinding and crushing food between their surfaces

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

crown

A

part of the tooth which is visible above the gum

its shape depends on the job which it has to do

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

neck

A

the part of the tooth covered by the gum

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

root

A

the part of the tooth which is fixed into the jawbone

  • root canal lets blood in to feed the tooth
  • as human teeth gets bigger, this canal becomes narrow, reducing the blood supply until the tooth stops growing
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

cement

A

bone like tissue which covers the root

fixes the root of the tooth into a bony socket in the jaw

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

fibrous tissue

A

joins the cement to the bone

they allow the tooth a little movement in its socket, so reducing the risk of breakage

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

pulp cavity

A

hollow space in the centre of the tooth

contains pulp which carries nerves to give the tooth ‘feeling’ and blood vessels to feed the tooth

cavity is lined with cells which make the dentine

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
39
Q

dentine

A

hard as bone (softer than enamel, inside enamel)

most of the tooth made of dentine

running through are tiny channels which carry the raw materials needed to build up and feed the tooth

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
40
Q

enamel

A

the hardest material in the body

forms the tough outer covering of the crown of the tooth

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
41
Q

fluoride does what for teeth?

A

strengthens the enamel of the teeth, giving them a hard exterior surface

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
42
Q

tooth decay is caused by

A

bacteria in plaque, which changes sugar to acid that attacks the enamel and dentine of the tooth

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
43
Q

what happens if particles of sugary food are left between your teeth

A

Bacteria in plaque changes the sugar into acid because they are respiring anaerobically

Acid attacks the enamel on the surface of a tooth and this starts off tooth decay

When the enamel is worn away, acid will attack the dentine

If the cavity reaches the pulp cavity it will cause a severe toothache, an abscess may form in the root

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
44
Q

acid can make your gums

A

red and swollen

45
Q

dentine is not ____ and dissolves ____

A

dentine is not acid resistant and dissolves easily

46
Q

holes formed in the teeth are called ?

A

dental cavities/caries

47
Q

describe the process up to swallowing food

A

• incisor and canine teeth bite into chunks
premolar and molar grind into smaller pieces
• mixed with saliva, moistened, rolled into a bolus and pushed to back of mouth (pharynx) and swallowed
• epiglottis closes over opening of trachea (glottis), preventing food from going into the lungs

48
Q

if food goes the wrong way it

A

triggers a reflex cough

49
Q

salivary glands make saliva which contains

A

mucus: slimy substance that lubricates the passage of the food bolus down the throat
amylase: the enzyme that catalyzes the breakdown of starch to maltose

50
Q

after leaving the stomach the food is called

A

chyme

51
Q

chyme is pushed along the tube by what process?

A

peristalsis

52
Q

peristalsis (bolus)

A

involves a wave of muscular contractions that squeeze the food bolus, carrying it down the oesophagus to the stomach

53
Q

describe peristalsis

A

circular muscles contract (CC) & longitudinal muscles relax (LR) BEHIND bolus to PUSH it along

circular muscles relax (CR) and longitudinal muscles contract (LC) to widen the oesophagus to allow the bolus of food to move along

54
Q

does peristalsis also occur in the s and l intestine

A

yes but to lesser extent

55
Q

where does amylase work best, where does it stop

A

neutral pH

stops once bolus reaches the stomach

56
Q

food arrives from the oesophagus into the stomach through the _______

A

cardiac sphincter

57
Q

stomach is located —-

A

left of the body, just below the diaphragm

58
Q

Roles of the stomach

A
  1. physical churning, mixing, and breaking up of food from the bolus (MECHANICAL digestion)
  2. destruction of bacteria, fungi etc that might enter the body with the food
  3. the CHEMICAL digestion of PROTEINS

muscular sac

59
Q

glands of the stomach produce

A

gastric juice and mucus

60
Q

what does the gastric juice contain and what does it do

A

the protease enzyme pepsin which breaks down proteins into shorter chains of amino acids called peptides
(word eq: ..?)

hydrochloric acid
- optimum pH for pepsin, kills potentially harmful microbes

61
Q

whats needed for chemical digestion of proteins in the stomach

A

hydrochloric acids and pepsin (enzyme) from gastric juices

62
Q

how does mechanical digestion in the stomach happen

A

muscular contraction (peristalsis)

63
Q

how does chyme leave the stomach

A

through the pyloric sphincter

64
Q

what coats the stomach’s walls and what does it do

A

mucus coats the stomach’s walls

forms protective barrier between it and gastric juice which would damage tissues

65
Q

food leaving the stomach enters the ___

A

duodenum

66
Q

which two important associate organs have ducts leading into the duodenum

A

pancreatic duct- bringing pancreatic juice from the pancreas

the bile duct- bringing bile from the gall bladder, where it has been stored after being made by the liver

67
Q

what does the entry of chyme into the duodenum trigger

A

release of bile and pancreatic juice down their ducts

68
Q

bile and pancreatic juice are ___ because —

pH

A

alkaline because the food from the stomach has a low pH which makes it unsuitable for enzymes in the small intestine

69
Q

bile contains ___ ____ and _____

A

bile pigments and cholesterol

70
Q

why is the breakdown of fats by bile mechanical and not chemical digestion?

A

the molecules aren’t chemically changed by enzymes

71
Q

How does the emulsification by bile salts aid chemical digestion by enzymes?

A

The smaller droplets have more surface area for the enzymes to act on

72
Q

what does pancreatic amylase do

A

continues breaking down any remaining starch molecules to maltose

73
Q

maltase

A
  • enzyme found in the membranes of the epithelium cells that line the small intestine
  • breaks down the double sugar maltose into the single sugar glucose which is absorbed
74
Q

what does trypsin do

A

breaks down proteins down into amino acids

is protease enzyme like pepsin

75
Q

why is trypsin needed in the small intestine instead of pepsin

A

optimum pH of pepsin is acidic (1.5-2.5) but the conditions of the intestine are alkaline

76
Q

esophagus

A

the muscular tube that connects the mouth and stomach

77
Q

pancreas

what does it produce and where are they released

A

produces trypsin, amylase and lipase enzymes

releases these into the small intestine

78
Q

small intestine

A
  • produces protease (trypsin), amylase, and lipase enzymes to complete digestion
  • where nutrients are absorbed out of the alimentary canal into the body
  • where most of the water is absorbed into the body
  • it has two parts – the duodenum and the ileum
79
Q

gum

A

soft tissue that surrounds and protects the tooth and bone

80
Q

where is amylase made

A

salivary glands, pancreas, small intestine

81
Q

where are proteases made

A

stomach, pancreas, small intestine

SPSI

82
Q

where are lipase made

A

pancreas, small intestine

83
Q

describe the process of diarrhoea

A

diarrhoea is watery faeces
• occurs when water can’t be absorbed from the intestines/ extra water secreted onto them
• loss of water
-> dehydration
-> loss of salt, glucose and other important minerals
- affects the functioning of the body, can cause the
body to lose more water
long time -> serious dehydration, maybe death

84
Q

how does ORT work

what are ORSalts usually made of

A

drinking water that contains relatively large amounts of dissolved salt, glucose, and other important minerals

• brings body’s levels of water, salt, glucose and other important minerals back up

needs to be given regularly until diarrhea stops

ORS made of mixture of salts, glucose and cooled boiled water
• diarrhea: sodium rich intestinal secretions lost before they can be reabsorbed
• glucose: imp energy source, can’t be absorbed properly from gut without enough sodium

85
Q

what are absorbed into the lacteals and drained into the lymphatic system

what happens to them after

A

fatty acids, glycerol and fat-soluble vitamins absorbed into lacteals

this transports them to a blood vessel under the coller bone where they join the general circulation

86
Q

(vili) what substances are absorbed into the ___ network

A

sugars such as glucose, amino acids, minerals and water-soluble vitamins absorbed into the capillary network in the vili

87
Q

(vili) are the materials actively or passively transported

A

both

88
Q

adaptions of small intestine

A
  • long tube with ridged walls covered with finger-like projections called villi and these have cells with projections called microvilli -> large SA
  • rich blood supply- large SA for exchange
  • lacteals which help with the absorption of less soluble vitamins
89
Q

lacteal

A

digested fats go here and are taken away into the lymphatic system

90
Q

what do glands (small intestine) make to do what

A

cells make digestive juice to add to the food in the small intestine

91
Q

why is defecation egestion rather than excretion

A

excretion is the removal of newly created chemicals which is not the case for defecation

92
Q

what are absorbed into lacteals and what happens to them

A

fatty acids, glycerol and fat-soluble vitamins absorbed into the lacteals and drained into the lymphatic system

transports them to blood vessel under coller bone -> join general circulation

93
Q

how is cholera treated

A

ORT, patients drink mixture of water, glucose and salts to rehydrate themselves

94
Q

(vili) what do the capillaries do and what is a result of this

A

carry absorbed molecules away

  • > maintains high concentration gradient
  • allows more molecules to diffuse into capillaries
95
Q

Salivary amylase

A

6.8

96
Q

Pancreatic protease (trypsin)

A

7.5-8.0

97
Q

Stomach protease (pepsin)

A

1.5-2.0

98
Q

Describe the structure of a villus

A
  • Central lacteal used for transporting fatty acids and glycerol in the
    lymph fluid
  • Lots of capillaries to absorb nutrients into the blood
  • Thin wall to minimise the diffusion distance
99
Q

Give 2 examples of protease enzymes

A

Pepsin and trypsin

100
Q

Where in the alimentary canal is lipase secreted?

A

pancreas

101
Q

How can dental decay be prevented?

A

-Brush teeth regularly and thoroughly with
fluoride containing toothpaste twice a day for
roughly 2 minutes

  • Control diet and limit the consumption of
    sugary food and drinks
102
Q

How are villi adapted for absorption?

A
  • Thin walls
  • Large surface area
  • Good blood supply close to the surface
103
Q

How is the ileum adapted to absorption?

A

The ileum is lined with villi and microvilli
which provide a large surface area for
absorption

104
Q

What is the function of the duodenum?

A

The duodenum receives food directly
from the stomach and uses enzymes
and chemical digestion to break the food
down

105
Q

Describe the passage of food through the alimentary

canal

A

Mouth → oesophagus → stomach →
small intestine → large intestine →
rectum

106
Q

What is the difference between the alimentary canal and the digestive system?

A

The alimentary canal involves the tubes
that the food passes through whereas
the digestive system also includes digestive glands

107
Q

What is an ion channel?

A

They are proteins that span cell membranes that
allow charged molecules to pass through the
membrane

108
Q

ileum

A

second section of the small intestine
main site of absorption of the products of digestion
enzymes in the epithelial lining digest peptides and maltose

109
Q

other than enzymes what does pancreatic juice contain

A

sodium hydrogen carbonate which partially neutralizes gastric juices from the stomach

bio (8 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions