Digestive System

Question 1

What is a cell?

Answer 1

The smallest unit of life Makes up all living things

Question 2

What is a tissue?(Give an example)

Answer 2

A group of similar cells working together
i.e. group of nerve cells makes a nerve (tissue)

Question 3

What is an organ?(Give example)

Answer 3

A group of tissues working together
i.e. muscle tissue and nervous tissue both needed in the heart

Question 4

What is an organ system?

Answer 4

A group of organs working together to carry out an essential bodily function

Question 5

What is a nutrient?

Answer 5

A substance which is needed for an organism to survive and be healthy

Question 6

What are the 3 macronutrients?

Answer 6

Fats (lipids)
Protein
Carbohydrates

Question 7

What is the function of the digestive system?

Answer 7

To break down and absorb nutrients from food

Question 8

What is the role of enzymes in the digestive system?

Answer 8

Speed up the breakdown of macronutrients (fats, proteins and carbs)

Question 9

What enzyme digests fats (lipids) and what is produced?

Answer 9

Enzyme: Lipase
Products: Fatty acids
and glycerol

Question 10

What enzyme digests protein and what is produced?

Answer 10

Enzyme: Protease

Products: Amino acids

Question 11

What enzyme digests starch and what is produced?

Answer 11

Enzyme: Amylase

Products: Glucose

Question 12

What 2 organs produce all 3 digestive enzymes?

Answer 12

Pancreas
Small intestine

Question 13

What organ produces only amylase?

Answer 13

Salivary glands

Question 14

What organ produces only protease?

Answer 14

Stomach

Question 15

Explain the effect of temperature on enzyme activity?

Answer 15

Increasing temperature, increases enzyme activity because there is more kinetic energy and more collisions between molecules

After the optimum temperature, enzyme activity decreases because the enzyme is denatured

Question 16

Explain the effect of pH on enzyme activity?

Answer 16

• Each enzyme works best at optimum pH

• Increasing or decreasing pH, enzyme activity decreases because the enzyme is denatured

Question 17

What is the active site?

Answer 17

Where the substrate joins to the enzyme

Question 18

Describe what happens when an enzyme is denatured?

Answer 18

The enzyme changes shape and can no longer function

Question 19

What jobs do enzymes have outside the digestive system?

Answer 19

Speed up other reactions such as

• Building large molecules from small

• Respiration

• Photosynthesis

Question 20

The small intestine is an exchange surface. What does this mean? Give 3 examples.

Answer 20

Exchange surfaces increase the rate of absorption of nutrients into an organism

Roots in plants (water)

Small intestines (glucose, amino acids,
fatty acids, glycerol)

Lungs (oxygen)

Question 21

How is the small intestine adapted for its function?

Answer 21

Villi make large surface area

Good blood supply

Walls one cell thick

Question 22

Where is bile made?

Answer 22

Liver

Question 23

Where is bile stored?

Answer 23

Gall bladder

Question 24

Describe the function of bile.

Answer 24

To speed up fat digestion by lipase

Question 25

Explain how bile speeds up fat digestion by lipase in the small intestine.

Answer 25

Neutralises stomach acid which creates optimum
pH for lipase to work

Breaks down fat into
smaller droplets (emulsifies) so it has a larger surface area

Question 26

Name the digestive system organs

Answer 26

mouth, esophagus, stomach, small intestine, pancreas,gall bladder,liver,large intestine, rectum and anus

Question 27

What is an Enzyme?

Answer 27

Biological catalyst:
Speeds up reactions without getting changed or used up in the reaction itself