Organisation

Organelle

smallest structural and functional unit of a cell

cells

one of several structures with specialised functions

tissue

a group of cells working together for common goal/function

Organ

a group of tissues working together for a common goal/function

organ system

a group of organs working together working together for a common goal/function

organism

an entire living thing (animal/plant)

organise tissue, cell, organs, organism , organ system and organelle from smallest to largest.

organelle

cell

tissue

organs

organ system

organism

Explain what the function of a muscular tissue is

A group of cells that work together for to contract and release a muscle

do all tissues contain one type of cell

no tissues can be made up of different cells

What are epithelial cells?

the overlayer of cells

stomach

muscular walls pummel food. Hydrochloric acid kills bacteria

Gall bladder

stores bile

pancreas

produces a number of enzymes like amylase, protease and lipase

large intestine

excess water is absorbed back into the body here

rectum

where feces is stored before it's removed

Oesophagus

tube that connects the mouth to the stomach

small intestine

nutrients from our food is absorbed into our blood stream

liver

produces bile

salivary glands

produces enzymes like amylase in the mouth

appendix

It stores good bacteria and releases it when it's needed

enzymes

biological catalysts that does not get used up produced by living things and made from proteins

Metabolism

a set of life sustaining chemical reactions in an organism

Catalysts

substances that speed up chemical reactions e.g. amylase

activation energy

the least amount of energy used for a reaction to take place

which substrate does amylase (carbohydrase) break down

breaks down starch into glucose

where is amylase produced

produced by salivary glands, pancreas and small intestine

where is amylase found

found in mouth and small intestine

which substrate does protease (pepsin) break down

breaks down proteins into amino acids

where is protease (pepsin) produced

produced by pancreas small intestine and stomach

where is protease (pepsin) found

found in small intestine and stomach

which substrate does lipase break down

breaks down fats into fatty acid and glycerol

Where is lipase produced?

produced by pancreas and small intestine

Where is lipase found?

found in small intestine

using the lock and key theory explain how enzymes breakdown starch in the body (3 marks)

a specific type of enzymes breaks down starch called amylase. Amylase breaks down starch by bumping into into starch in the salivary glands and since the shape of starch as a substrate compliments the active site of amylase, forming the enzyme-substrate complex, amylase then breaks it down in glucose which can be used for aerobic respiration

State the two functions of bile

neutralises the excess hydrochloric acid on the food (from the stomach) that gets transported to the small intestine.

Bile emulsifies the fats increasing the surface area to allow lipase to breakdown fats faster

Define emulsification

the physical breakdown of large drops of fats into smaller droplets.

Define optimum temperature

where the rate of reaction is highest due to increased kinetic energy

What does denature mean?

when the enzyme loses shape meaning its active site no longer fits the shape of the substrate, therefore it can't breakdown the substrate

what environment does protease (pepsin) work best in?

in an acidic environment

what environment does amylase (carbohydrase) work best in?

in an alkaline environment

what environment does lipase work best in

in an alkaline environment

amylase required practical (pH levels)

1) Place one drop of iodine solution into each depression on the spotting tile.

2) Label 2 test tubes with pH to be tested (4 and 7).

3) Measure 2cm3 of one of the buffered pH solutions with 5mL measuring cylinder and pour into each test tube (rinse measuring cylinder after use).

4) Use the pipette to place 1 cm3 of amylase into each buffered pH solution.

5) Use another pipette to add 3 cm3 of starch to each amylase/buffer solution.

6) Immediately start the stop clock and leave it on throughout the test.

7) Mix using a glass rod.

8) After 30 seconds, remove one drop of the mixture with a glass rod. Place this drop on the first depression of the spotting tile with the iodine solution. The iodine solution should turn blue-black

9) Rinse the rod with distilled water.

10) Use the glass rod to remove one drop of the mixture every 30 seconds. Put each drop onto the iodine solution in the next depression on the spotting tile. Rinse the glass rod with water after each drop. Continue until the iodine solution and the amylase/buffer/starch mixture remain orange.

Benidicts test

test for reducing sugars

is sugars present solution changes from light blue to red (strong concentration of sugars), green (low concentration of sugars), orange (moderate concentration of sugars)

-requires water bath above 60 degrees

Iodine solution test

test for starch

if starch present solution changes from orange to blue

Biuret test

test for proteins

is protein present solution change from blue to purple

Ethanol test

test for lipids

if lipids present a white cloudy layer will form

-ethanol is highly flammable and harmful

Sudan III test

test for lipids

red top layer= fat present

red solution= no fat present

functions of blood

Supply oxygen and nutrients to the cells for aerobic respiration

Provide essential nutrients to cells such as amino acids , glucose and fatty acids

Removing waste materials such as lactic acid carbon dioxide. and urea

Blood is an example of a

tissue

The four components of blood

plasma

red blood cells

white blood cells

platelets

red blood cell

makes up 45% of blood

carries oxygen and heomglobin

no nuclues to provide more space for heomglobin proteins

bi concave shape for an increased surface area

white blood cells

makes up <1% of blood

Fights infections

large surface area

Platlets

makes up <1% of blood

Very sticky- able to form a clot

Made from the fragments of old cells

Plasma

makes 55% of blood

Carries many substances

Largest part to the blood

substances carried by plasma

Glucose

Water

Amino acids

Fatty acids

Lactic acid

Mineral ions

Proteins

What is the function of the circulatory system

transports nutrients and oxygen to body cells and removes waste products.

What is cardiovascular disease?

a disease of the heart and blood vessels

If the blood vessel is the coronary artery- the disease is called coronary heart disease (CHD)

what happens in cardiovascular diseases

When low density lipoproteins (LDL)/ plaque/ fatty deposits build up in the walls of the coronary arteries that run to your heart

Explain how coronary heart disease can cause a heart attack

Coronary disease can lead to a build up of fatty deposits over time this can complete block the coronary arteries restricting blood flow to the heart starving the heart of oxygen. The heart muscle is unable to respire causing a heart attack

statins

drugs used to lower cholesterol in the bloodstream

advantages of statins

cheap treatment

no operation needed

disadvantages of statins

can cause side effects (such as liver damage)

Stents

Used to widen a blocked artery or hold open an artery weakened by a heart attack

advantages of stents

Effective treatment

disadvantages of stents

requires surgery

Artificial pacemakers

Used to treat irregular heart beat

The pace maker send electrical pulses to your heart to keep it beating regularly and not too slowly

Advantages of artifical pacemakers

Very effective

Only requires minor surgery

disadvantages of artificial pacemakers

Requires an operation

May require replacement

Valve-replacement: biological

Leaky valves which is dangerous as they do not keep blood flowing in the right direction

advantages of Valve-replacement: biological

no medicine needed

disadvantages of Valve-replacement: biological

Only lasts 12 to 15 years

Might not use due to ethical reasons (comes from animals)

Valve-replacement: artificial'

Leaky valves which is dangerous as they do not keep blood flowing in the right direction

advantages of Valve-replacement: artificial'

Readily available and will not be rejected by the body

disadvantages of Valve-replacement: artificial'

Requires long term medication to prevent blood clots

Heart transplant

Last resort for people with heart failure

Faulty heart removed and a donor heart is fitted in a long operation

advantages of heart transplant

new heart can last many years

disadvantages of heart transplant

Donor needed

Donor heart may be rejected

Immunosuppressants drugs need to be taken for the rest of your life

Religious objections

Artificial heart

Used to treat heart failure - possibly while waiting for a donor heart

advantages of artifical heart

Reduces deaths waiting for donor heart

No need to match donor

No need for immunosuppressant drugs

disadvantages of artifical heart

Blood clotting

Expensive

Must stay in hospital whilst fitted

Explain why a person with a leaking heart valve has difficulty exercising

Leaky valves can do not keep blood flowing in the right direction allowing the blood that is coming into the heart and the blood leaving the heart to mix this

leads to reduced volume of blood being pumped around the body leading to less amount of oxygen being carried to cells and muscles leading to less aerobic respiration

so less energy released which leads to shortness of breath and tiredness therefore physical exercise can become more difficul

what is health

The state of physical and mental wellbeing

communicable disease

a disease that is spread from one host to another (contagious)

e.g- flu

noncommunicable disease

Diseases that are not spread. Diseases of long duration and generally get worse over time

e.g.-asthama

What is a risk factor?

risk factors are things that are linked to an increases in the likelihood that a person will develop a certain disease during their lifetime

What is cancer

Cancer is the result of mutated cells that lead to uncontrolled rapid growth and division

malignant cancer

Not in a membrane, can break off and travel around the blood stream spreading the cancer

Causing secondary tumours

Dangerous and can be fatal-they are cancer

benign cancer

Held within a membrane- not cancerous

Stays in one place (doesn't spread)

Treatment for cancer

surger, radiotheraphy, chemotherapy

radiotherapy

Radiations beams target cancer cells, killing them

Chemotherapy

chemicals used to stop cells developing and killing them

Surgery

cut tumour out

Carcinogens

substances that cause cancer