Nutrients and the Digestive System

Question 1

What are the five main groups of nutrients?

Answer 1

Carbohydrates, Proteins, Lipids, Vitamins, Minerals

Question 2

Define Nutrients

Answer 2

Nutrients are substances found in food that are essential for our bodies to function.
Nutrients provide energy and materials for cell function, growth and repair.

Question 3

What are carbohydrates

Answer 3

Carbohydrates are sugars, starches and fibre found in foods like fruit, vegetables, grains and dairy products.
Carbohydrates can be simple in structure called monosaccharides and disaccharides like glucose and sucrose.

Question 4

What is the role of carbohydrates

Answer 4

Carbohydrates supply energy to cells for cellular respiration

Question 5

What is protein.

Answer 5

They are building blocks essential for cell growth and repair in tissues like muscle, bone, hair and skin.
They are also important chemical like enzymes, hormones, and carriers like haemoglobin.
Proteins are made of smaller units call amino acids.

Question 6

What are Lipids

Answer 6

Lipids are molecules also known as fats and oils
Lipids have important roles in cell membranes and some chemicals like hormones
They can also provide and store energy
Lipids are made up of two parts – glycerol and fatty acids

Question 7

What are vitamins

Answer 7

Vitamins are organic nutrients that are required in only small amounts
They are essential for many processes in the cells
A lack of some vitamins can lead to vitamin-deficiency diseases like scurvy (vitamin C) and rickets (vitamin D).
Vitamins are found in a wide variety of foods like fruit, vegetables, eggs, dairy, fish and grains.

Question 8

What are minerals

Answer 8

minerals are inorganic nutrients required in small amounts.
They also play an important role in many cell processes like nerve and muscle function and the immune system.
Minerals are essential for building structures like haemoglobin, bone and teeth.

Question 9

What are the non-nutrients and what do they do?

Answer 9

Food contains additional important components that are not nutrients.
They are not used for energy, growth or repair but are essential for health.
These are water and fibre.

Question 10

Describe water as a essential non-nutrient

Answer 10

Water makes up 2/3 of our body
It is essential for life
It makes up our cell cytoplasm and blood
It helps remove wastes from the body, keeps skin healthy, joints moving and regulates body temperature
Water is found in food like fruit, vegetables and dairy

Question 11

Describe fibre as an essential non-nutrient

Answer 11

Fibre plays an important role in digestive function
Fibre is a carbohydrate (cellulose) that cannot be digested by humans
It helps material to move through the digestive system properly
If material moves through too slowly, too much water can be removed which causes constipation
This can cause damage to the digestive system
Fibre is found in food that comes from plants

Question 12

What is digestion

Answer 12

In order to obtain nutrients from the food we eat, it needs to be broken down into small molecules so it can be absorbed and use by the cells of the body

Question 13

What are the two types of digestion

Answer 13

Mechanical and Chemical

Question 14

What is mechanical digestion

Answer 14

Mechanical digestion breaks food down physically (large pieces into small pieces)
Mechanical digestion includes chewing which occurs in the mouth and churning which occurs in the stomach

Question 15

What is chemical digestion

Answer 15

Chemical digestion breaks down food using enzymes and breaks food into its building blocks e.g. proteins are broken into amino acids so they can pass into the bloodstream

Question 16

What is digestive enzymes

Answer 16

Digestive enzymes are essential to complete the process of breaking down food into small particles

Question 17

What are the three digestive enzymes

Answer 17

Amylases, proteases, and lipases

Question 18

What is the role of amylases

Answer 18

Digest carbohydrates
Found in the mouth & small intestine

Question 19

What is the role of proteases

Answer 19

Digest proteins
Found in the stomach & small intestine

Question 20

What is the role of lipases

Answer 20

Digest lipids
Found in small intestine

Question 21

What is the order of digestion

Answer 21

Food > Mouth, Oesophagus > Large intestine > Small intestine > Stomach

Question 22

Describe the mouth

Answer 22

In the mouth food is chewed by the teeth with the help of the tongue.
Saliva adds moisture to make it easy to swallow.
Saliva also contains amylase which begins to breakdown carbohydrates.
The chewed up food is called a bolus.

Question 23

Describe the oesophagus

Answer 23

When food reaches the back of the tongue, we swallow.
This pushes the food bolus down the oesophagus to the stomach.
The movement of the oesophagus is called peristalsis and is waves of muscular contraction.

Question 24

Describe the stomach

Answer 24

The stomach is very acidic as it also produces hydrochloric acid which activates the protease and destroys foreign material.

Question 25

Describe the small intestine

Answer 25

The small intestine is where the nutrients from food will pass into the blood stream.
The small intestine has special structures called villi to maximise absorption of nutrients.

Question 26

What is the bolus

Answer 26

a small, rounded mass of a substance, especially of chewed food at the moment of swallowing:

Question 27

Describe the liver

Answer 27

The liver has many roles important to the body.
For digestion, it produces bile which assists the mechanical digestion of lipids.
It breaks up large globules of fat into small ones in a process called emulsification.
Bile is stored in the gall bladder before being released into the small intestine.

Question 28

Describe the pancreas

Answer 28

The pancreas makes all three types of digestive enzymes – amylases, proteases and lipases.
These are added into the small intestine to complete chemical digestion of carbohydrates, proteins and lipids.

Question 29

Describe the large intestine

Answer 29

When the majority of nutrients have been absorbed from the material in the small intestine, the remaining material passes into the large intestine.
Water is absorbed from the undigested material and turns into a more solid form called faeces.
This can be stored in the rectum before passing out of the body through the anus.