Aqa Biology Unit 1 Flash Cards

Front 1

Nucleus

Back 1

Contains genetic material which controls the activities of the cell

Front 2

Cyptoplasm

Back 2

most chemical processes take place here, controlled by enzymes

Front 3

Cell Membrane

Back 3

Controls movement of substances into and out of the cell

Front 4

Mitochondria

Back 4

Most energy is released by respiration here

Site of Respiration, ATP production

Front 5

Ribosomes

Back 5

Protein synthesis happens here

Front 6

Golgi Apparatus

Back 6

Processes and packages new lipids and proteins. It also makes lysosomes

Front 7

Rough Endolplasmic Reticulum

Back 7

Folds and processes proteins that have been made at the ribosomes

Front 8

Smooth Endoplasmic Reticulum

Back 8

Synthesizes and processes lipids

Front 9

Types of Diffusion

Back 9

Diffusion

Osmosis

Active Transport

Front 10

Diffusion

Back 10

Movement of particles from a high concentration to a low concentration down a concentration gradient

Front 11

Osmosis

Back 11

Net diffusion of particles from a solution with a high water potential to a solution with a low water potential down a concentration gradient

Front 12

Active Transport

Back 12

Uses Energy to move molecules and ions against a concentration gradient

Front 13

Facillitated Diffusion

Back 13

Some larger molecules (eg. Amino Acids, Glucose) and ions can't diffuse directly through the phospholipid bilayer of the cell membrane.

Insted they diffuse through carrier proteins or protein channels in the cell membrane

Front 14

Carrier Proteins

Back 14

Move large molecules into or out of the cell.

1. Large molecule attatches itself to the carrier protein

2. Then the protein changes shape

3. This releases the molecules on to the opposite side of the membrane

Front 15

Protein Channels

Back 15

Form pores in the membranes for charged particles to diffuse through

Different protein channels facillitate the diffusion of different charged particles

Front 16

Properties of Fluid Plasma Membrane

Back 16

1. Membrane is a good barrier against most water soluble molecules

2. The membrane contorls what enters and leaves

3. The membrane allows cell communication

4. The membrane allows cell recognition

5. The membrane is fluid

Front 17

Prokaryotic Cell

Back 17

Single celled organisms

Front 18

Eukaroytic Cell

Back 18

Multi cellular organism with specialised organelle inside

Front 19

Enzymes

Back 19

They are biological catalysts, they speed up the reaction without being used up

They work best at the optimum temperature of 37C

They have an optimum pH which depends on which enzyme they are

Front 20

Enzymes

Back 20

They are proteins

Substrates fit into the enzyme at the active site

Substrates will only fit into the active site that has a complimentary shape to each other

If the shape of the enzyme changes, its active site may no longer work

Front 21

Enzymes

Back 21

Extreme pH and High temperature may cause the enzyme to become denatured

Front 22

Inspiration

Back 22

External intercostal muscles contract

Internal intercostal muscles relax

Ribs move up and out

Diaphragm contracts and flattens

Volume in the thorax increases

Pressure in the thorax decreases, Air moves in

Front 23

Expiration

Back 23

External intercostal muscles relax

Internal intercostal muscles contract

Ribs move down and in

Diaphragm relaxes and becomes curved

Volume in the thorax decreases

Pressure in the thorax increases, Air moves out

Front 24

Pulmonary Ventilation

Back 24

Tidal Volume x Ventilation rate

Front 25

Fick's Law

Back 25

Front 26

Cardiac Output

Back 26

Stroke Volume x Heart rate

Front 27

Heartbeat Control

Back 27

Electrical impulses travel through this route

AVN->Collagen Tissue->SAN->Bundle His->Purkinje Fibres

Front 28

Cardiac Cycle (Short form)

Back 28

Atrial Systole - Ventricles Relaxed, Atria Contract

Ventricular Systole- Ventricles contract, Atria Relaxed

Diastole- Ventricles Relaxed, Atria Relaxed

Front 29

Cardiovascular Disease:

Atheromas

Back 29

Endothelium is usually smooth and unbroken

Damage occurs to the endothelium and white blood cells and lipids clump together to form fatty streaks

Over time , this builds up to for a fibrous plaque

This partially blocks the lumen and restricts blood flow and increases blood pressure

Front 30

Cardiovascular Disease:

Aneurysm

Back 30

Atheroma plaques weaken and damage arteries as well as increasing blood pressure

When blood travels through a weakened artery at high pressure it may push the inner layers of the artery though the outer elastic layer to form a balloon like swelling- an aneurysm

This aneurysm may burst causing a haemorrhage

Front 31

Cardiovascular Disease:

Thrombosis

Back 31

An atheroma plaque can rupture the endothelium of an artery

This damages the artery wall and leaves a rough surface

Platelets and fibrin accumulate at the site of damage and form a blood clot

This blood clot can cause a compete blockage of the artery or it can be blocked and dislodge another artery elsewhere

Front 32

Antigens

Back 32

Antigens are molecules which are identified as foreign and trigger an immune response

Front 33

Phagocytosis

Back 33

A phagocyte recognises the antigens on a pathogen

Phagocyte engulfs the pathogen

Pathogen is now contained in a phagocytic vacuole in the cyptoplasm

A lysome releases hydrolytic enzymes to break down the pathogen

The phagocyte then presents the pathogen's antigens- it sticks the antigen on its surface to activate other immune system cells

Front 34

Pathogens

Back 34

Pathogens Cause disease by either releasing toxins or damaging the host tissue

Front 35

T Cells

Back 35

T cells are cell mediated responses

If an antigen is present with a complimentary shaped receptor, the T Cell is stimulated increases is size and starts to divide

Front 36

T Cells

Back 36

When T Cells divide, they :

Kill infected cells

Stimulate phagocytes to engulf pathogens

Stimulate B cells to divide

Develop memory cells that enable a rapid response in the future

Front 37

B Cells

Back 37

When the antibody of a B Cell meets a complimentary shaped antigen, it binds to it

This, together with substances released from T Cells, activates B Cells

Th activated B Cell divides to form plasma cells

Front 38

Plasma Cells

Back 38

They make more Antibodies to a specfic Antigen

Front 39

Immune Response can be Memorised

Back 39

Primary Response- Slow, takes time to produce right antibodies needed to bind it , Memory Cells produced which record specific antibodies needed to bind to the antigen

Front 40

Immune Response can be Memorised

Back 40

Secondary Response- Same pathogen enters, quicker response, memory b cells divide into plasma cells and produce the right antibody to the antigen. Memory T Cells divide into the correct type of T Cells to kill the cell carrying the antigen