Extra biology Flashacrds (Required)

Question 1

What does mascular tissue do?

Answer 1

Can contract to bring about movement.

Question 2

What does glandular tissue do?

Answer 2

Comtains secretory cells that can produce and release substances, such as enzymes and hormones.

Question 3

What does epithelial tissue do?

Answer 3

Covers the outside of your body as well as your internal organs.

Question 4

What is a tissue?

Answer 4

A geoup of cells with similar structure and function working together.

Question 5

What are organs?

Answer 5

Organs are collections of tissues. Each organ contains several tussues, all working together to perform a specific function.

Question 6

What process is the stomach involved in?

Answer 6

The digestion of food.

Question 7

What does the stomach contain that allows it to digest food?

Answer 7

Muscular tissue- to churn the food and digestive juices of the stomach together

Glandular tissue- to produce the digestive juices that break down food

Epithelial tissue- covers the inside and the outside of the organ

Question 8

What are the two important functions of the pancreas?

Answer 8

• It makes hormones to control blood sugar

- It makes some of the enzymes that digest food

Question 9

What are organ systems?

Answer 9

Groups of organs that all work together to perform specific functions.

Question 10

Why do we need a digestive system?

Answer 10

The food we eat is made up of large insoluble molecules. Your body cannot absorb and use these molecules. They need to be broken down or digested to form smaller, soluble molecules

Question 11

How long is the digestive system?

Answer 11

Between 6 and 9m long

Question 12

Examples of glands in the digestive system and what do they do?

Answer 12

The pancreas and salivary glands make and release digestive juices containing enzymes to break down food.

Question 13

What two things happen in the small intestine?

Answer 13

Where food is digested
Enzymes break down the large insolube food molecules into smaller, soluble ones. Once there, they get transported in the bloodstream around your body.

Question 14

How is your small intestine adapted for this?

Answer 14

It is adapted to have a very large surface area as it is covered in villi.
It has a good blood supply
It has short diffusion distances to the blood vessels. This greatly increases diffusion and active transport from the small intestine to the blood.

Question 15

What happens to the food after the small intestine?

Answer 15

• The muscular walls of the small intestine squeeze the undigested food onwards into your large intestine
• This is where water is absorbed from the undigested food into your blood
• The material left forms the faeces
• These are stored and then pass out of your body theough the rectum and anus

Question 16

What happens to enzymes at 40 C?

Answer 16

The protein structure of the enzyme is affected by the high temperature. The long amino chains begin to unravel, and as a result, the shape of the active site changes. The substrate will no longer fit in the active site. The enzyme is now denatured and can no longer act as a catalyst, so the rate of reaction deops dramatically. Work best at 37 C

Question 17

What is the effect of pH on enzyme action?

Answer 17

A change in pH affects the forces holding the folded protein chains inplace. If there is a change, the shape of the molecule and specific shape of the active site is lost, so the enzyme no longer acts as a catalysts.

Question 18

Pepsin works best in an ….?

Answer 18

Acidic pH

Question 19

Why does your stomach produce a thick layer of mucus?

Answer 19

It coats the stomach walls and protects them from being digested by the acid and the enzymes.

Question 20

What happens if someone develops a stomach ulcer?

Answer 20

The protecting mucus is lost and acid production may increase. The lining of the stomach is then attacked by the acid and the protein-digesting enzymes, which can be very painful.

Question 21

Where is bile stored until needed?

Answer 21

The gall bladder

Question 22

Through what is bile squirted on to food in the stomach?

Answer 22

Bile duct

Question 23

Why does bile neutralise stomach acid?

Answer 23

To provide the alkaline conditions necessary for the enzymes in the small intestine to work most effectively.

Question 24

What can happen when gall stones form?

Answer 24

They can block the gall bladder and bile duct. They can cause terrible pain and stop bile being released onto the food and reduce the efficiency of digestion.

Question 25

Features of arteries?

Answer 25

Thick walls
Small lumen
Thick layer of muscle and elastic fibres

Question 26

Features of veins?

Answer 26

Relatively thin walls
Large lumen
Often have valves

Question 27

Features of capillaries?

Answer 27

Walls a single cell thick

Tiny vessel with narrow lumen

Question 28

What is meant by double circulatory system?

Answer 28

• One transport system carries blood from your heart to your lungs and back again. This allows gas exchange to take place.
• The other transport system carries blood from your heart to all other organs of your body and back again.

Question 29

What are the skin defences?

Answer 29

• Cover your body and act as a barrier. This orevents bacteria nd viruses reaching the tissue beneath. If your damage or cut your skin, the platelets act.
• Your skin prodcues antimicrobial secretions to destroy pathogenic bacteria
• Healthy skin is covered with microorganisms that help keep you healthy and act as an extra barrier to the entry of pathogens

Question 30

What are the defences of the nose?

Answer 30

-Nose full of hairs and prodcue mucus which both trap particles in the air that may contain pathogens. If in a pollited area, the mcicus when you blow your nose is blackened, showing it works.

Question 31

Defences of the trachea and bronchi?

Answer 31

They secrete mucus that traps pathogens from the air. The lining of the tubes covered in cilia, tiny like hair projections. The cilia beat to waft the mucus up to the back of the throat where it is swallowed.

Question 32

Defences of the stomach?

Answer 32

Produces acid and this destroys the microorganisms in tye mcucus you swallow, as well as the majority of the pathogens you take in through your mouth in your food and drink.

Question 33

Describe how some white blood cells produce antibodies?

Answer 33

These are special chemicals that target particular bacteria or viruses and destroy them. You need a unique antibody for each type of pathogen.

Question 34

When your white blood cells have produced antibodies once against a praticular pathogen, …?

Answer 34

They can be made very quickly if that pathogen gets into the body again, stopping you getting the disease twice.

Question 35

Why does the mucus look green?

Answer 35

Some white blood cells contain green enzymes. These whute blood cells destroy cold viruses and any bacteria trapped in the mucus of your nose when you have a cold. The dead white blood cells, along with the dead bacteria, and viruses, are remived in the mucus, making it look green.

Question 36

Magnification formula

Answer 36

Image size divided by actual size

Question 37

1 micro metre in pico m

Answer 37

1,000,000

Question 38

1 micrometre to nano metre

Answer 38

1000

Question 39

Digestive system

Answer 39

Learn diagram

Question 40

Do that practice thing from today and%%%

Answer 40

Bio past paper in bag