Biology Test-2018-06-01(suggested answer)

Biology Test(suggested answer)

Date:2018-06-01

Class: ___________(    )             Name: ____________    Mark: _________

Section I: 30%

1. List the functions of different types of teeth:

   (i) incisor: biting and cutting the food

   (ii) canine:  tearing flesh

   (iii) molar:  crushing and grinding the food

2. Finish the following table to show the chemical digestion:

Digestive glands	Digestive juices	Enzymes involved	Site of Action	Functions(actions) of the enzyme(s)
Salivary gland	Saliva	Salivary amylase	Mouth cavity	Starch - > maltose
Gastric gland	Gastric juice	pepsin	Stomach	Protein ->peptides
pancreas	Pancreatic juice	Pancreatic amylase Pancreatic proteases lipase	Duodenum	Starch -> maltose Protein->peptides ->amino acid
Intestinal glands	Intestinal  juice	Carbohydrases proteases	ileum	Disaccharides -> monosachharides

Section II: 70%

1. Fill in the blanks to show the relationship between the features and functions:

Structures	Related features	Functions
Enamel	Hard / made up of calcium salts	Protect the tooth from wearing
Pulp cavity	Contain blood vessels	Provide nutrient and oxygen to the tooth
Stomach	Contain hydrochloric acid	Kill bacteria in the food
Wall of alimentary canal	Contain mucus	Prevent the wall from digestion by proteases

2. List the site(s) in the alimentary canal where carbohydrates are digested

Mouth cavity, duodenum, ileum

3. List the site(s) in the alimentary canal where proteins are digested

Protein, duodenum, ileum

4. List the site in the alimentary canal where carbohydrates begin to be digested

Mouth cavity  

5. List the site(s) in the alimentary canal where proteins begin to be digested

Stomach

6. List the site(s) in the alimentary canal where lipids begin to be digested

doudenum

7. State the importance of bile to digestion:  

Bile contain bile salt. Bile salt can emulsify the larger oil droplets into small oil droplets to increase total surface area of lipid for the lipase to act on more efficiently

8. If we lost our incisor，what can we do according to the following consideration?

   (i) the tooth itself:_replace the tooth with a fake incisor

   (ii) the function of the tooth:__use a knife to cut the food

  (iii) the importance of the tooth:___eat food with smaller sizes

9  A cell belongs to a living thing, should have all living characteristics. Fill in the   blanks below to show the relationship between the structures and the living      characteristics.

Structures	Functions	Related living characteristics
Mitochondrion	Break down food to provide energy	Respiration
Chloroplast	Carry out photosynthesis	Nutrition
Vacuole	Collect metabolic wastes in plant cells	excretion

10. List the name(s) of the digestive glands related to the digestion of starch.

Salivary gland, pancreas

11. List the name(s) of the digestive glands related to the digestion of protein.

Gastric glands, pancreas, intestinal glands

12. Explain the reason why taking in too much protein will lead to overweight.

   Excessive protein in the body will turn into lipid, the lipid can be stored under the skin and leads to overweight

13. How to prove the presence of vitamin C?

   Add the sample solution into the DCPIP with fixed volume, if the colour of the DCPIP change from deep blue to colourless, the sample solution contains vitamin C.

14. How to prove the presence of vitamin C in orange juice?

  Add the orange juice solution into the DCPIP with fixed volume, if the colour of the DCPIP change from deep blue to orange the orange juice solution contains vitamin C.

15. State the effect on digestion if the stomach is cut half.

   Stomach contain pepsin which can catalyse the protein into peptides. If the stomach is cut half, the digestion of protein will be affected.