2.4 nutrition Flashcards
1
Q
definition of nutrition
A
obtaining nutrients to provide energy to maintain life functions, and matter to create and maintain structure
2
Q
2 types of nutriton
A
autotrophs (producers)
heterotrophs
3
Q
examples of autotrophs
A
plants/phytoplankta
4
Q
examples of heterotrophs
A
paramecium/animals
5
Q
what do autotrophs do
A
use simple inorganic materials such as water and carbon dioxide to manufacture energy. containing complex organic compounds
6
Q
what do heterotrophs do
A
depend on autotrophs for their food supply. they consume complex organic food material, which must be broken down before its used
7
Q
what do autotrophs provide
A
food for all other forms of life
8
Q
photosynthesis in terms of food
A
light is the source of energy for the production of food.
9
Q
2 types of bacteria
A
photosynthetic
chemosynthesis
10
Q
photosynthetic bacteria…
A
use a pigment called bacteriochlorophyll (blue/purple) which needs light to photosyntheise
11
Q
chemosynthesis bacteria….
A
can synthesise organic compunds from inorganic compounds in the absence of light
12
Q
what are the organisms who aren’t dependent on photosynthesis reliant on
A
chemosynthesis
13
Q
process of chemosynthesis
A
process where they use chemicals in hydrothermal vents to produce energy
14
Q
properties of heterotrophic nutrition
A
- connot make their own organic food
- must consume organic compound made by autotrophs
- known as consumerz
15
Q
4 types of heterotrophic nutrition
A
-holozoic feeders
-saprophytes
-parasites
-mutualism
16
Q
explain holozoic feeders…..
A
-include nearly all animals
-they take food into their bodies and break it down (digestion)
- most have specialised digestive systems
- digestive materials is then absorbed into the body tissue
17
Q
herbivores
A
solely plant materials
18
Q
carnivores
A
feed on other animals
19
Q
detrivores
A
animals that feed on dead/decaying material
20
Q
explain saprophytes
A
-feed on decaying matter
-don’t have a specialised digestive system
- include some bacteria/ALL fungi
-secrete enzymes
-food source is absorbed by diffusion across the cell membrane
- important in global ecosystems
21
Q
where to saprophytes secrete enzymes
A
happens at the tip of the structure, the hypha
22
Q
why are saprophytes important in global ecosystems
A
play a major part in decomposing dead plant materials and recycling nutrient (nitrogen)
23
Q
explain parasites…..
A
-organisms that feed on/in other living organisms. host always suffers harm to some degree
-highly specialised and adaptive
24
Q
example of parasites
A
tapeworm,malarial parasite
25
explain mutualism
or symbosis, involves a close association between members of two separate species. both benefit from the relationship
26
example of mutualism
digestion of cellulose by microorganisms in the gut of a herbivore
27
Example of unicellular organisms
Amoeba
28
Explain the digestion in unicellular organisms
-large SA to volume ratio
- May take in food by diffusion, facilitated diffusion, active transport
- May take in food by endocytosis, enzymes digest food in bachelors
- Exocytosis removes indigestion remains
29
Explain multicellular (with single body opening) organisms
- cylindrical with tentacles surroundings its mouth
-extracellular digestion by enzymes
-products of digestion absorbed and remains egested in the mouth
30
Explain the digestive system of a shark
-short thick intestine pathway (high protein diet)
- Wide oesophagus
- large liver
31
Digestive system of salamender
Long small stomach
thin oesophagus
32
Digestive system of a liver
Bumpy intestine
Large curved stomach
33
Digestive system of a pigeon
Large crop (storing foods on long journeys)
Long intestine pathway
Gizzard (to break down food, they don't have teeth)
34
Function of serosa
Protection, reduced friction between but and other organs
34
Properties of serosa
Outermost layer
Tough connective tissue (fibrous tissue, collagen)
35
What are the four layers of the gut wall
-serosa
-muscle
-submucosa
-mucosa
36
Properties of muscle
Inner circular muscle and outer longitudinal muscle that works together
37
Function of muscle layer
Peristaltic
Behind ball of food, circular contract and longitudinal relax
38
Properties of the submucosa layer
Connective tissue
Blood and lymph vessels, nerves
39
Function of the submucosa layer
vessels remove absorbed products of digestion. Nerves co-ordinate peristalsis
40
Properties of mucosa layer
Outermost layer
41
Function of mucosa layer
Epithelium secretes mucus. In some regions it secretes digestive juices and in others it absorbs digested food
42
What is physical digestion
Cutting and crushing by teeth
Mixed with saliva and mucus to soften the food and lubricate it
43
What is chemical digestion
In the mouth saliva contains saliva contains amylase to digest starch to maltose
44
Role of the oesophagus
Carried food to the stomach
45
What do oesophagus contain
Goblet cells
Circular and longitudinal muscle
46
What do goblet cells do
Produce mucus to lubricate the food
(found in mucosa)
47
What do circular/longitudinal muscles do
Allow peristalsis
48
What is peristalsis
Wave like motion pushing food down through the gut
49
What are found in the mucosa
Contains gastric pits
50
What do gastric pits contain
Oxyntic cells
Zymogen cells
Goblet cells
51
What do oxyntic cells contain
Produce HCL
52
What do Zymogen cells produce
Produce pepsinogen
53
What do goblet cells produce
Produce mucus
54
How is pepsinogen activated
By HCL to make pepsin
55
What does pepsin do
Breaks peptide bonds between amino acids in a polypeptide chain
56
What is the function of the stomach
protein is digested, breaks large polypeptides into smaller polypeptides
57
Enzymes involved in the stomach
Endopeptidase
(Pepsinogen)
58
Special features of the stomach
- sphincter muscles,
- Wall muscles contract rhythmically (circular and longitudinal)
- Gastric pits are glands in the mucosa
59
first part of the small intestine called
duodenum
60
role of the first section of the small intestine
-receives secretion from the liver and pancreas
-has bile from liver (stored in the gall bladder) bile salts emulsify lipids to increase SA
-aids lipase digestion
61
what are pancreatic juices secreted by
islet cells (glands in pancreas)
62
what does the duodenum contain
enzymes
63
3 types of enzymes in the duodenum
trypsin
exopeptidase
amylase/lipase
64
what is trypsin an example of
endopeptidase
65
how is trypsin made
trypsinogen turned to trypsin by enterokinase
66
what do exopeptidase do
hydrolyse peptide bonds on the end of peptides, from the free amino end or the free carboxyl end
67
what does the duodenum also contain
sodium hydrogen carbonate (alkaline to neutralise stomach acid)
68
what is the Brunner's gland
where alkaline secretions released
69
second part of the small intestine
ileum
70
2 roles of the ileum
digestion and absorption
71
what do the epithelial cells at tips of villi do
-produce endopeptidase and exopeptidase (dipeptides to amino acids)
- digest disaccharides into monosaccharides
72
what is maltose broken down into
2 alpha glucose by maltase
73
what is sucrose broken down into
glucose and fructose by sucrase
74
what is lactose broken down into
glucose and galactose by lactase
75
second role of ileum
absorption
76
what does the ileum contain
villi with microscopic projections called microvilli
77
what do the microvilli do
give an even larger surface area for absorption (by diffusion, FD and AT)
78
how do amino acids go from the lumen to epithelial cells
AT with sodium ions, uses ATP
(CARRIER PROTEINS)
79
how do aminon acids get from epithelial cells into the capillary
FD- channel/carrier protein. then go to the liver via the hepatic portal vein
80
how is glucose transported from the lumen to epithelial cells
CT- with sodium ions
81
how is glucose transported from the epithelium cells into capillary
Sodium ions active tranport
glucose FD (some AT)
they will go by FD until equilibrium, AT to get the rest of the glucose into the blood
82
how are fatty acids and glycerol transported from the lumen to epithelial cells
Difusion, reform to become triglycerides again
83
how do fatty acids and glycerol go from epithelial cells into capillary
go into lacteals instead and are passed to the lymphatic system
84
what happens to the molecules once they are digested
glucose and amino acids are transported via the hepatic portal vein to the liver
fatty acids and glycerol diffuse into the epithelial cells, return to triglycerides. go to the lacteal and are carried via the lymphatic system
85
what is the large intestine made up
caecum, appendix, colon and rectum
86
what happens in the large intestine
-undigested food, mucus, bacteria and dead cells pass into the cell
- does not have villi, not as many as the ileum
- where water and mineral absorption happens
vitamin K and colic acids are secreted by mutualistic microbes living there
87
what is folic acid important for
the nervous system
88
dentation of a carnivore
- incisors
- canine
-premolars
-carnassials
-jaw (mandible)
89
properties of incisors
carnivore
sharp
90
job of incisors
carnivores
tear muscle from bone
91
properties of canines
carnivore
large, curved, pointed
92
job of canines
carnivores
to tackle prey
93
properties of premolars and molars
carnivores
sharp points (cusps)
94
job of premolars and molars
carnivores
to cut and crush
95
properties of carnassial
carnivores
specialised cheek teeth that act like scissor blades
96
job of carnassial
carnivores
takin muscle of bones
97
explain the jaw of a carnivore
lower jaw moves vertically and can open widely. jaw muscles are powerful. protrusions in skull for muscles to attach to bone
98
dentation of herbivores
-incisors
- canines
-dental pad
-diastema
-premolars
-molars
-jaw
99
properties of incisors
herbivores
bottom jaw only
100
role of incisors
herbivores
slices through plants
101
properties of canines
herbivores
indistinguishable from incisors
102
role of canines in herbivores
slices through plants
103
properties of dental pad
herbivore
leathery pad on the upper jaw
104
job of dental pad
herbivores
where food gets pulled across for slicing
105
properties of diastema
herbivores
gaps between front teeth and premolars where tongue and cheek operate
106
properties of premolars
herbivores
side teeth
107
role of premolars
herbivores
chewing plants
108
properties of molar
herbivore
they interlock. grinding action occurs. continue to grow
109
describe the jaw
Lowe jaw muove side to side
no strong muscles are needed
110
what is a ruminant
a cud-chewing herbivore that has mutualistic microbes in the rumen
111
what is a rumen
part of stomach
112
what does bacteria get out of the mutualistic relationship
food and a place to live
113
what does their diet mainly consist of
grass (cellulose)
114
what do animals rely on to break down cellulose
rely on mutualistic microbes living in their gut to secrete enzymes e.g fungi, bacteria and protocista which live in a chamber called the rumen
115
what are the 4 stomachs of a cow
rumen
reticulam
omasum
abomasum
116
explain the rumen
what does it contain
contain microbes that digest cellulose
cellulose breaks down into glucose
117
explain the reticulum
fermented grass become cud and goes back to the mouth
118
explain the omasum
from the mouth it goes to the omasum, where water is reabsorbed
119
explain the abomasum
true stomach
protein is digested by pepsin
120
what are parasites
-highly specialised organism that live in/other organisms (host) and so obtain nourishment at the expense of host organisms
121
what do parasites gain from other organisms
nutrition-which is absorbed from the hosts tissues and fluids or the intestine
122
2 types of parasites
ECTOparasites
ENDOparasites
123
what are ectoparasites
live on the outside of the body
head louse
124
what are endoparasites
live inside the host
e.g roundworms, tapeworms and blood flukes
125
what problems do tapeworms face
-digestive juices
-peristalsis
-pH of gut
- host immune system
- death the host
126
structural modifications to aid survival of a tapeworm
-suckers and a double row of curved hooks attaching to duodenum wall (for attachment)
-a thick body covering (cuticle) to protect from immune system
- production of inhibitory enzymes on the surface of the body segments (protection from digestion)
- tapeworm has flattened body to increase SA to volume ratio and is can absorptionb food (nourishment)
127
reproductive strategies of the tapeworm
1) hermaphrodite - each body segment have male and female gametes. the gut cannot accommodate 2 tape worms (asexual reproduction
2) large number of eggs are produced
mature segments can contain up to 40,000 eggs to increase chance of survival
128
