Download 2015 Prelim Biology 1 5 Schedule 15 File

ASSESSMENT SCHEDULE 2015
AS90929 [Biology 1.5] Demonstrate understanding of biological ideas relating to a mammal(s) as a consumer(s)
Q
1.( a)
A
M



( b)


N0
Describes diffusion of nutrients into the
bloodstream through villi / labelled picture
of villi
Describes diffusion of nutrients from the
blood into the muscle cells
Describes the heart pumps the blood to
circulate nutrients around the body
Assimilation is the movement of digested
food molecules into the cells of the body
where they are used.
Aerobic respiration is the conversion of
chemical energy (glucose) into useable
energy in the cell (ATP)/release of energy
from food in cells
N1
= 1 points
N2
=2 points
A3
= 3 points
E





QUESTION ONE
Explains how the nutrients are absorbed
into capillaries in the villi of the small
intestine
Explains now nutrients travel from
capillaries to veins then to the heart, into
arteries then capillaries and finally into
muscle cells.
Explains heart tissue assimilates amino
acids to build new proteins/Amino acids
are required to make muscle fibres and/or
enzymes.
Full word equation for aerobic respiration
provided
Energy is required so that the heart can
transport nutrients (oxygen and nutrients)
to all the cells of the body/transport
wastes (CO2) to the lungs for elimination
A4
= 4 points
M5
= 3 points
M6
= 4 points


Assimilation of amino acids is required
to synthesise muscle fibres which
contract when the heart beats/enzymes
that catalyse reactions such as respiration
in the heart cells. This pumping allows
nutrients and wastes to be circulated
through the body.
Assimilation of glucose from the blood
into the heart cells is used in aerobic
respiration to provide energy for heart
muscle cells to contract, this causes
blood to flow bringing oxygen and
nutrients to the heart AND taking carbon
dioxide and wastes to the lungs.
E7
= 1 point
E8
= 2 points
2. (a)


(b)






N0
Physical digestion is the breakdown of food
into smaller/soluble pieces so that they can
be absorbed
Herbivores primarily gain nutrition from
plant material/they graze or forage
OR Carnivores primarily gain nutrition
from animal material/they trap, hunt prey
OR Omnivores gain nutrition from a mix of
plant and animal sources. (2 of the above 3
required)

Structure:
Carnivores have a larger stomach than
herbivores/omnivores OR ruminants have
multiple stomachs
Herbivores have a longer small intestines
than carnivores/omnivores
Herbivores have a caecum

Function:
The stomach is the site of meat/protein
digestion
The small intestine is the main site for
chemical digestion of carbohydrates, fats
(and proteins).
The caecum is the site for digestion of
cellulose (plant cell wall).
N1
= 1 – 2 points
N2
= 3 points
A3
= 4 points

QUESTION TWO
Herbivores have larger flat molars for
grinding plant cells/diastema to provide
space for continued chewing or
regurgitation of food/hard plate in place
of top incisors to act as a cutting
board/incisors for cutting
Carnivores have sharp incisors for cutting
flesh/large canine teeth for trapping,
killing prey, puncturing vital
organs/sharp molars for cutting rather
than grinding.
Stomach is the site for acid/enzyme
digestion of protein. Carnivores eat large
meals of mostly protein so require a large
stomach.
 Some herbivores (ruminants) have
multiple stomachs for digesting plant
material. A large amount of plant
material is required for large herbivores
to gain enough energy.
 Small intestine is the main site for
chemical digestion of carbohydrates, fats
(and proteins). Since omnivores and
herbivores gain nutrition from
carbohydrates/mixed diets their intestines
are longer than carnivores to provide time
for the digestion of these nutrients.
 Carnivores/have a reduced caecum
(vestigial) since they gain their nutrition
from protein which is not digested in the
caecum.
A4
M5
M6
= 6 points
= 4 points
= 5 points



Structures identified and linked to the
process of digesting cellulose/cell walls
which are very tough and require a great
deal of chewing to increase surface are
for chemical digestion/release the
contents of the cells
Structures in carnivores related to either
killing and processing of large animals
AND increased surface area for chemical
digestion
Carnivores eat mainly protein so require
a large stomach for acid digestion of
proteins into amino acids. They only
require a short intestine since most
digestion occurs in the stomach.
Carnivores have a greatly
reduced/vestigial caecum and cannot
digest cellulose. (gives reasons for
differences in all 3 organs)
 Mammals do not produce enzymes to
digest cellulose/cell walls so herbivores
have a large caecum which houses
bacteria which secrete enzymes to help
with cellulose digestion. Longer
intestines provide more time for
carbohydrate digestion. Multiple
stomachs to enable efficient
digestion/eating their own waste to
extract nutrients from microbial
breakdown in the intestines.
E7
E8
= 3 point
= 4 points
QUESTION THREE

3. a)


(b)
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Chemical digestion involves enzymes, not
all the enzymes are in the mouth.
Salivary glands only produce the enzyme
which digests starch.
Bile is produced by the liver to help digest
fats/breaks up fats
Bile neutralises stomach acid


(c)

Correctly completes 2 rows of the table
Organ
Type of
Food
Enzyme
pH
Mouth
Carbohydrate
(Starch)
Amylase
7
(neutral)
Stomach
Protein
Pepsin
(Protease)
2-4
(acidic)
Small
Intestine
Lipids
(Fats)
Lipase
8
(basic)
Bile emulsifies fats and oils so that
enzymes from pancreatic juices can more
easily come into contact with their
substrate (fats and oils)/increases the
surface area to enable more efficient
digestion by enzymes
Bile salts help adjust the pH to enable fat
digesting enzymes/lipase to function

(d)

N0
Judgement
Statement
Score Range
N1
= 1 point
Not
Achieved
0–8
N2
=2
points
A3
= 3 points
Explains how different pH levels
(numerical or low, high, acidic, neutral,
basic / alkaline) provide optimum
conditions for enzyme activity, in
different parts of the digestive tract, using
a named example of an enzyme.
Explains how enzymes are affected by
pH in respect to not functioning when pH
is not optimal or denaturing
A4
= 4 points
M5
= 2 points
M6
= 3 points

Elaborates by relating the digestion of
different food types to different digestive
enzymes requiring specific pHs to
function efficiently AND correctly links
a specific enzyme to its associated food
type and relates the efficiency of
digestion to the appropriate conditions in
a named organ.
 Elaborates that enzymes are present in
lower levels in some parts of the
digestive system because enzymes
become denatured/are unable to bind to
their specific substrate when pH is not
optimal.
 Elaborates on where enzymes are
produced and secreted, identifying
gastric glands as the source of pepsin in
the stomach and the pancreas as the
source of lipase, amylase and peptidase
enzymes in the small intestine.
E7
E8
= 2 points
= 3 points
Achieved
Merit
Excellence
9 - 13
14 - 18
19 - 24