Nat 5 Digestive system Homework 2
- The function of the villi is to increase the surface area for
Aabsorption
Bprotection
Cacid production
Dperistalsis
- 100 g of baked beans contains 4.5 g of protein.
How many grams of beans would provide a daily protein requirement of 81g?
A5.5 g
B18 g
C364.5 g
D1899 g
- Which line in the table below describes correctly the changes in food due to digestion?
Changes in food
Molecule size / Solubility
A / decreases / increases
B / decreases / decreases
C / increases / decreases
D / increases / increases
- Digestion takes place in animals
Aand allows insoluble molecules to pass directly through the wall of the small intestine.
Bas enzymes cannot act on insoluble molecules
Cand makes insoluble molecules soluble to allow absorption
Dand allows food to be passed along the gut by peristalsis
- Which of the following lists all the elements that are present in every protein molecule?
Acarbon, hydrogen, oxygen, nitrogen
Bcarbon, oxygen, nitrogen
Ccarbon, hydrogen, oxygen, sulphur
Dcarbon, hydrogen, oxygen
- Stomach muscles relax and contract in order to
Arelease enzymes
Baid absorption of digested products
Crelease mucus and acid
Dmix food with digestive juices
- Which of the following molecules is absorbed from waste food in the large intestine?
Aglucose
Bwater
Camino acids
Dglycerol
- Bile is produced in the liver and stored in the gall bladder.
Bile is released into the small intestine where it
Adigests fat
Bdigests glycogen
Cemulsifies fat
Demulsifies glycogen
- Which food group contains the most energy per gram?
Acarbohydrate
Bprotein
Cfat
Dvitamins
The next two Questions refer to the diagram of the digestive system below.
11.Which labelled arrow identifies the small intestine?
12.Which labelled arrow identifies where water is absorbed?
13.Lipase is an enzyme found in the small intestine. Lipase speeds up the breakdown of fat. Full cream milk contains a high proportion of fat.
Three test tubes were set up as shown in the diagrams below.
milk + boiled milk + milk +
lipase + lipase + boiled lipase +
pH indicator pH indicator pH indicator
The pH of the contents of each test tube was recorded at the start and again 15 minutes later.
What changes in pH took place?
AThe pH decreased in each test tube
BThe pH increased in each test tube
CThe pH decreased in tubes X and Y and did not change in tube Z.
DThe pH increased in tubes Y and Z and did not change in tube X.
14.The diagram below shows a single villus from the small intestine.
15. Which food molecules are absorbed into the lacteal?
Aamino acids and glycerol
Bglucose and amino acids
Cfatty acids and glycerol
Damino acids and fatty acids
16. The diagram shows the apparatus used to investigate the energy of fat.
Which of the experiments shown below allows a valid comparison to be made between the energy content of fat and protein?
17. (a)The bar graph below shows the energy content of equal masses of carbohydrate, fat and protein food types.
Identify food type A and give a reason for your answer.
(b)Biuret reagent is used to identify protein.
State the colour of a positive result for this food test.
(c)Name the element found in protein that is not present in carbohydrates and fats.
(d)A healthy human diet contains a variety of minerals.
Name one of these minerals and describe how it is used by the body.