Biology organsiton

What is tissues?

groups of cells with similar structure and function

What is an organ?

A group of different tissues that work together to perform a certain function.

What is an organ system?

A group of organs that work together to perform a specific function

Give an example of an organ system?

Digestive system

What is the order of the digestive system?

mouth, oesophagus, stomach, small intestine(Liver and pancreases help_, large intestine, rectum, anus

Name the 3 main nutrients

Carbohydrates, Protein, Lipids

Why can't protein be digested without being broken down first?

Because these (Carbohydrates and Lipids)molecules are too large.

What do enzymes do?

speed up chemical reactions

What does the mouth do in digestion?

mechanically breaks down food

How do the salivary glands help in digestion?

There is the amylase enzyme in the gland which help break down starch into sugars.

What is the role of the oesophagus?

It carries food from the mouth to the stomach

What does the stomach contain to help digest protein?

Hydrochloric acid.

What does hydrochloric acid do?

kills bacteria and activates pepsin (enzyme for protein)

Why does the stomach produce the action of "Churning"

It turns the food into a liquid to increase the surface area of the enzymes to digest.

What does the small intestine absorb?

food molecules

What do the walls of the small intestine release?

Enzymes to continue the digestion of protein and lipids

What does the liver release?

bile

What does bile do?

Neutralises stomach acid and emulsifies fats

Where is bile stored?

gallbladder

What does the pancreas do?

produces enzymes for digestion and starts digestion of lipids

What does the large intestine absorb?

water

Where does the faeces go trough?

rectum then anus

What is the extra glucose used for?

respiration

What is an enzyme?

A biological catalyst that speeds up chemical reactions

What is the groove called in enzymes?

Active site

What is the name of the thing that "connects" to the active site?

substrate

Why are enzymes specific?

Each type of enzyme has an active site that only fits one specific substrate

What is protein made up of?

long chains of amino acids

Which enzymes break down proteins?

proteases

Where is protease found?

Stomach, pancreas, small intestine

What does protease do?

breaks down proteins into individual amino acids

Why does protease break down protein?

So that the protein can be absorbed into the bloodstream

What does optimum temperature mean?

temperature at which the enzyme works best--for humans, this is 37°C

What happens to enzymes as the temperature gets higher (not too high)

Enzymes that's moving faster so there are more collison so this mean that the activity is increasing.

What happens when to temperature of an enzymes increases too much?

It becomes denatured and no longer catalyses the reaction.

Give 2 reasons for an enzymes to become denatured.

If the conditions are too acidic or alkaline, and if the temperature is too high.

What does starch consist of?

glucose molecules

Which enzymes breaks down carbohydrates?

Carbohydrase

Which enzymes breaks down starch

Analyse

What does starch produce when broken down?

simple sugars

Where amylase is found?

salivary glands and pancreas

What are lipids made of?

glycerol and fatty acids

Which enzymes break down lipids?

lipase

Where is lipase found?

Pancreas and small intestine

What does it mean when you say bile emulsifies lipids?

It break down large drops of fat into smaller ones

Is bile acidic or alkaline?

alkaline

How long is the small intestine?

5 metres

What is the small intestine lined with?

villi

What does villi do?

increase surface area

What does villi have on it?

microvilli

What does microvilli do?

increases surface area for absorption

How does villi having a good blood supply help?

It rapidly removes products of digestions which increased the cncentartion gradient.

Does villi have a thick or thin membrane? What does this do?

Thin membrane, it creates a short diffusion path.

Name 3 ways villi helps with absorption in the small intestine.

- It has microvilli

- Good blood supply

- Thin membrane

What happens to the molecules that are not absorbed by diffusion in the small intestine?

They are then absorbed by active transport.

What is the purpose of the circulatory system?

Transport oxygen and nutrients to the body.

What are the three main things the circulatory system relies on?

Blood, heart,Blood vessels

What are the atria and ventricles separated by?

valves

What are the atria and the ventricles?

They are chambers

how many atriums are there in the heart?

2 (right and left)

How many ventricles are in the heart?

2 (right and left)

Are the ventricles at the top or at the bottoms of the heart?

bottom

Are the atriums at the top or at the bottoms of the heart?

top

What is the role of the heart?

To pump blood around the body

Is the blood from the pulmonary vein oxygenated or deoxygenated?

Oxygenated (Because it comes from lungs)

Is the blood from the vena cava oxygenated or deoxygenated?

Deoxygenated- coming from the loop the body

What the 1st step in the circulatory system?

Blood flow into the heart through the vena cava and the pulmonary vein.

What is the 2nd step in the circulatory system?

The atria contract pushing the blood down into the the ventricles.

What the 3rd step in the circulatory system?

Ventricles contract and blood gets pushed up out of the pulmonary artery (Lungs) and the aorta (Body).

What does an artery do?

carries blood away from the heart

What does a vein do?

carries blood toward the heart

What do the valves in the heart do?

prevent blood from flowing backwards

Why is the left side of the heart thicker?

It has to pump blood all around the body not just to the lungs

What is a pacemaker?

A group of cells in the right atrium wall that control the resting heart rate.

What happens if the pacemaker in your heart is faulty?

It can get replaced by an artificial pacemaker.

What does an artificial pacemaker do?

correct irregularities in the heart rate using electrical impulses.

What i the main role of red blood cells?

Carry oxygen from the lungs to the cells in the blood

What is the oxygen from RBC used for?

Respiration

How does the oxygen the RBC carries get to our cells/tissues?

Oxyhaemoglobin travels around the body to the tissues and then splits back into oxygen and haemoglobin and then the oxygen gets diffused into the tissues/cells.

Do red blood cells have a nucleus?

nope

Name 2 adaptations of red blood cells.

- Doesn't have a nucleus- which gives it more space for Oxyhaemoglobin

- Shaped like a concave disk- gives it a larger surface area

Do white blood cells have a nucleus?

yep

What do phagocytes do?

engulf and destroy pathogens

What do antibodies do?

Bind to pathogens to help destroy them

What do antioxidants do?

neutralise toxins

Name 3 ways white blood cells defend us against pathogens

They have:

- Phagocytosis

- Antibodies

- Antitoxins

What are platelets?

Small fragments of cells

Do platelets have a nucleus?

nope

What is the role of platelets?

blood clotting

What would happens if we didn't have platelets

Cuts would result in excessive bleeding and bruising

What do platelets prevent from entering and how this help?

Microorganism- this prevents infection

What happens if you lose and an excessive amount of blood?

You can get artificial blood or get a blood transfusion.

What's a blood transfusion?

When you get blood from a blood donor

What are the advantages of using artificial blood?

It can only replace 1/3 of blood since it has no red blood cells