Organisation

Organelle

smallest structural and functional unit of a cell

cells

one of several structures with specialised functions

tissue

a group of similar 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 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)

Amylase breaks down starch by bumping into starch in the salivary glands. The 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 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 compliments 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.

Benedicts test

test for reducing sugars
is sugars present solution changes from light blue to brick red, orange or green
-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

Capillary function and adaptation

Allows substance to diffuse through the walls in and out the blood. Has thin walls for short diffusion pathways.

Veins

Carries deoxygenated blood back to the heart, has valves to prevent backflow. Large Lumen

Artery

Carries oxygenated blood away from the heart, has thick elastic walls to handle high pressure. Thick walls, small lumen, elastic fibres.

Functions of the blood

Supplies oxygen to cells (respiration). Provides essential nutrients to cells (amino acids, glucose). Removes waste materials (lactic acids).

Coronary heart disease

Where the coronary arteries become narrowed or blocked due to fatty deposits, reducing blood flow to the heart muscle and increasing the risk of heart attacks.

Stent treatment

Placing of a small mesh tube into a narrowed or blocked artery to keep it open and restore blood flow.

Statins

Reduces the livers production of cholesterol, which reduces fatty deposit build up.

Pacemaker

Helps regulate abnormal heart rhythms by sending electrical impulses to the heart. Placed in the right atrium.

Rate of blood flow=

volume of blood ml/time s

Health

the state of physical, mental, and social well-being, not merely the absence of disease.

Virus

Not cells, they enter cells and duplicate inside bursting the cell and releasing the virus.

Bacterial

Very small single prokaryote cells that produce toxins.

Protists

Single cells transferred by vectors

Pathogens

Microorganisms that cause disease, including viruses, bacteria, and some protists.

Communicable disease

Diseases that can easily spread.

Risk factors for cancer

Lack of exercise, smoking, drinking alcohol, taking drugs, poor diet, UV radiation.

Cancer

The result of mutated cells that lead to uncontrolled rapid growth and division.

Benign tumour

Not cancerous, held within a membrane

Malignant tumour

Not in a membrane, cancerous and can travel through the bloodstream.

Radiotherapy

beams target cancer cells, killing them

Chemotherapy

Chemicals used to stop cells developing, killing them

Surgery cancer

Cut the tumour out.

Trachea

Air passes through this passage to the lungs

Bronchiole

Each bronchus divides again to form smaller tubes. There are supported by rings of cartilage to prevent them collapsing

Bronchi

In the chest cavity the tube splits into 2.

Intercoastal muscles

Internal and external, help increase and decrease the thoracic cavity.

Ribs

protect vital organs in the chest

Alveoli

 Where gas exchange takes place by diffusion

Diaphragm

Contracts and flattens to aid ventilation.

Pleural fluid

The liquid found inside the lung.

Inhalation

Diaphragm contracts and moves down. Intercoastal muscles contract and move ribcage upwards and outwards. Chest expands, increasing the volume of the thorax. Pressure of the thorax decreases compared with the atmosphere. Air rushes into the lungs, causing them to expands.

Exhalation

Diaphragm relaxes and moves up. Intercoastal muscles relax and move ribcage downwards and inwards. Chest shrinks, decreasing the volume of the thorax. Pressure of the thorax increases compared with the atmosphere. Air rushes out of the lungs, causing them to decrease in size.

Waxy Cuticle

Prevents pathogens from entering and reduces water loss

Upper epidermis

Transparent layer to allow light to pass through for photosynthesis

Palisade layer

Contains many chloroplasts to absorb sunlight

Spongy mesophyll

Spongy air pockets to allow gases to diffuse through easily.

Stomata

Small gaps to allow gases and water to diffuse through

Guard cell

Cells used to open and close the stomata.

Xylem

Transports water to the leaf from the roots.

Phloem

Transports the sugars from the leaf to the rest of the plant.

Transpiration

The movement of water and mineral ions through the plant, via the xylem and evaporating out of the leaves.

Factors affecting transpiration

High temperature, windy conditions and increased light will increase transpiration and humidity will reduce transpiration.

Translocation

The movement of sugars from leaves to plant via the phloem.