Y10 Biology - Nutrition

What are lipids made up of?

Fatty acids (3 molecules) and glyceral (1 molecule)

What are carbohydrates (starch and glycogen) made up of?

simple sugars (glucose)

What are proteins broken down into?

They are polymers that are broken down into its monomers, amino acids

What is photosynthesis?

The process of making glucose from sunlight int eh leaves of the plant

What is the word equation for photosynthesis?

carbon dioxide + water --> glucose + oxygen

What factors can affect photosynthesis

Temperature, light intensity and concentration of carbon dioxide

What is the balanced chemical symbol equation for photosynthesis?

6CO2 + 6H2O --> C6H12O6 + 6O2

How does temperature affect photosynthesis?

As temp increases, the rate of photosynthesis also increases, although once the temp gets too high, the enzymes will start to denature.

How does light intensity affect photosynthesis?

The higher the light intensity, the rate of photosynthesis increases, as the distance between the light source and the plant increases, the light inrensity decreases.

How does carbon dioxide concentration affect photosynthesis?

Carbon dioxide is needed to make glucose, as the concentration of carbon dioxide increases, the rate of reaction also increases.

Why do leaves need magnesium

It is required for chlorophyll production, if there is a deficiency, it will cause the leaves to turn yellow

Why do leaves need nitrate

It is required to produce amino acids, if there is a deficiency, it will cause stunted growth and turn leaves yellow

What is the function of carbohydrates

A high energy source

What is the function of proteins

Used for growth and repair

What is the function of lipids

A high energy source and for insulation

What is the function of dietary fibre

To keep the food moving

What is the function of Vitamin A

Needed for vision, especially in the dark and for growth

What is the function of Vitamin C

Helps to absorb iron

What is the function of Vitamin D

Helps to absorb calcium

What is the function of calcium

For bone and teeth strength

What is the function of iron in the body

Needed for haemoglobin

What is the function of water

Needed for cell reactions to take place

What are the factors affecting energy requirements?

Age, activity level, pregnancy

How does age affect energy requirements?

More energy is needed as we approach adulthood, energy needs of adults go down as they age.

How does activity level affect energy requirements?

If you are more active then you will need more energy for movement

How does pregnancy affect energy requirements

More energy will be needed in order support growth of the baby, energy needs also increase due to the extra mass of the baby

What is the human alimentary canal

The alimentary canal is the passage food moves through once it has been eaten

What is the function of the mouth in the alimentary canal?

Teeth break up large food pieces into smaller pieces, amylase breaks down starch into glucose, salivary glands produce saliva to lubricate the broken down food so it can be easily swallowed

What is the function of the oesophagus in the alimentary canal

Tube from the mouth to the stomach, food moves down due to peristalsis (unidirectional wave-like contractions) created by circular muscles and longitudinal muscles that create a squeezing action

What is the function of the pancreas in the alimentary canal

Produces carbohydrase, protease and lipase enzymes, releases enzymes into the stomach and small intenstine

What is the function of the stomach in the alimentary canal

Gastric juice is released form stomach lining when food is detected, peristalsis also occurs here.

What is gastric juice made out of?

Pepsin: enzyme breaking down proteins<br>Hydrochloric acid: makes stomach acidic in order for pepsin to work and to kill any bacteria

What is peristalsis?

Unidrectional wave-like contractions created by muscles that push the food along

What is the function of the duodenum

It's the first part of the small intestine, carbohydrases, proteases and lipases digest food here, bile is released into the duodenum, peristalsis also occurs here.

What is bile and what is its functions

Bile is produced in the liver and stored in the gallbladder. It is alkaline to neutralise the hydrochloric acid which comes form the stomach. Enzymes in the small intestine have a more alkaline optimum pH than those in the stomach. It breaks down large drops of fat into smaller ones (emulsifies it). The larger surface area allows lipase to chemically break down the lipid into glyceral and fatty acids faster

What is the function of the ileum

Lined with villi (finger-like projections) to maximise absorption of digested soluble molecules into blood.

What is the function of the large intenstine in the alimentary canal?

Water is absorbed here in order to produce faeces, faeces is stored in the rectum and removed through the anus.

What happens to carbohydrates (starch) when digested?

Broken down by carobohydrases, starch is broken down into maltose by amylase, maltose is broken down into glucose by maltase

What happens to proteins when digested?

Broken down by proteases in the stomach and small intestine. Proteins are broken down into amino acids.

What happens to lipids when digested?

Broken down by lipases. Lipids are broken down into glyceral and 3 fatty acids.