digesve system x2

Question 1

what are the 3 parts of the large intestine

Answer 1

cecum
colon
rectum

Question 2

lipids

Answer 2

break down lipase into glycerol and fatty acids

Question 3

what would happen if there was no bile

Answer 3

most ingested lipids would be excreted as faeces

Question 4

fibirous plant eating animals that have 4 chamebered stomachs are called

Answer 4

ruminants

Question 5

what do the 4 chmabers of a rumiant do

Answer 5

the firts 2 chambers are responsible for ferminatiion of food before the food is regurgitated, chewed and passed into the second two chambers for chemicla digetsion.

Question 6

hydrchoirc acid do

Answer 6

kills pathoens that enter the stomahc

Question 7

optimal ph of pepsin

Answer 7

1.5

Question 8

how would ulcers befound

Answer 8

hydrochlroci acid kills pathogens and mucus membanres portcets the stomach lining from being digested by pepsin and form hydrochloric acid.

Question 9

how long does food stya in sotmach

Answer 9

4 hours

Question 9

stya in sotmach

Answer 9

absorb nutrients in the blood

Question 10

pyloric sphincter

Answer 10

muslce that seperates the duodenum from the stomach and holds the food in the stomahc until it is broken down

Question 11

bicarbondate

Answer 11

neutrlaises acidic food frm the stomahc the bring hte optium PH to 7.6

Question 12

Trypsin

Answer 12

protein digestiing enyzme that digests proteins into amni acids

Question 13

pancreal duct and bile duct function

Answer 13

pathway that allows secretiosn frm the pancreas into the small intestine

bile duct pathya where bile is secreted from the liver into the small inteistne

Question 14

Rats – no gall bladder. What does this say about their diet?

Answer 14

they are constnatly eating thus their body does need to store bile

Question 15

emulsification

Answer 15

bile breaks down fats into globules

Question 16

atwhat would happen if we didnt have bile

Answer 16

lipids would pass out in the feces.

Question 17

what kinda of digestion is emsulfication and what is its purpose

Answer 17

Emulsification is an example of mechanical digestion and serves to increase the surface area of the fats to enhance chemical digestion by lipase

Question 18

how do hervbires have adaptions that allow them to digest celluose

Answer 18

caecum contains bacteria that proudce na enznyme called cellulase which breaks down cellulose

Question 19

function of mucus

Answer 19

acts as a protective layer for the stomach against its own secreted enzymes and acids.

Question 20

The pyloric sphincter is damaged. What is the issue?

Answer 20

if they pylorci sphisnter is stomach the food will not be digested intothe stomach it will move directly from the stomach into the dondedmum, therefore food will not be digested properly and doneudmumwill be directly exposed to the hydrochloric, this will cause ulcers

Question 21

A herbivore such as a rabbit has a diastema instead of what? What is the purpose of this?

Answer 21

A herbivore such as a rabbit has a distema instead of canine teeth. As these animals lack canines which are required to tear food, the distema helps the other teeth work together to cut food. Distaema also allows the food to contiousnyi pass intothe oriel cavity whilst the herbivore is chewing.

Question 22

mesentery

Answer 22

a membrane that attaches the abodmiaml area to small itnesitne, therefore keeps the digetsive system in place.

Question 23

glycorptoein

Answer 23

sends and recievees signals and is involved in cell to cell adhesion

Question 24

Explain why scientists describe the plasma membrane as a ‘fluid mosaic’.

Answer 24

The plasma membrane is fluid because the phospholipids and other molecules can move around – they are not stiff or held in one place.1The plasma membrane is mosaic because many different molecules are embedded in the membrane.2

Question 25

Novel nanomaterials called ‘nanomedicines’ are being developed to diagnose and treat disease. To work, nanomedicines must enter a cell and interact with particular sub-cellular molecules. Nanomedicines gain entry into target cells through endocytosis.

Some scientists are concerned that after endocytosis, the nanomedicine may be destroyed by the cell. Explain how this might occur.

Answer 25

Lysosomes may fuse with the vesicle containing the nanomedicine.1Lysosomes contain enzymes which may destroy the nanomedicine.2

Question 26

When the leaves are folding,

Answer 26

potassium and chloride ions are pumped into flexor cells by active transport

Question 27

Explain the change occurring inside the guard cells and epidermal cells that leads to the net movement of water.

Answer 27

Guard cells become less turgid when water leaves, which occurs through osmosis.1For osmosis to occur quickly, ion channels open in the membranes of guard cells, and this leads to epidermal cells becoming hypertonic relative to guard cells.2Water will move from the area of low solute concentration (guard cells) to high solute concentration (epidermal cells).3

Question 28

The concentration of potassium ions, K+, in human blood plasma is approximately 4 mM. In the cytoplasm of red blood cells the concentration of these ions is around 100 mM. Explain how this difference in concentration is maintained.

Answer 28

Exemplar Response
This difference in concentration is maintained using active transport.1In active transport, ATP is used by specific protein pumps to transport K+ against its concentration gradient into the red blood cells, increasing the concentration of K+ in the cell. K+ is charged so cannot easily diffuse across the plasma membrane, meaning the cytoplasm remains hypertonic to the blood plasma in terms of K+