Biology 1 - Disease to Proteins

Question 1

Antigen

Answer 1

A protein that stimulates an immune response resulting in the production of antibodies

Question 2

Polymer

Answer 2

large molecules made by joining many identical monomers

Question 3

Primary structure of protein

Answer 3

The order in which amino acids are arranged

Question 4

Mitochondria

Answer 4

Deeply folded inner membrane

Perform aerobic respiration and produce ATP

Question 5

Cell fractionation and Ultracentrifugation

Answer 5

1. Homogenise cell to break it open
2. Filter solution
3. Centrifuge at low speed to separate largest organelle
4. Remove pellet and centrifuge at higher speed.
5. Repeat a higher speeds

Question 6

Why use a buffered solution in cell fractionation?

Answer 6

To prevent pH changes that could damage organelles by denaturation

Question 7

Why use an ice cold solution in cell fractionation?

Answer 7

To reduce enzyme activity

Question 8

Golgi Apparatus

Answer 8

• Layers of flattened fluid filled sacs
• Proteins/ lipids produced by ER pas through
• Sorts, modifies and packages molecules into vesicles

Question 9

Ribosomes

Answer 9

Found all over cell but mainly on Rough Endoplasmic Reticulum
Perform protein synthesis
Prokaryote: 70s
Eukaryote: 80s

Question 10

Rough Endoplasmic Reticulum

Answer 10

Encrusted with ribosomes

Site of protein synthesis

Question 11

Smooth Endoplasmic Reticulum

Answer 11

Synthesises lipids

Question 12

Secondary Protein Structure

Answer 12

Polypeptide chain folded into alpha helixes or beta pleated sheets

Question 13

Tertiary Structure of Proteins

Answer 13

3D shaped molecule made by hydrogen, ionic and disulphide bonds between R groups.
Disulphide bonds between cysteines only

Question 14

Lysosomes

Answer 14

Vesicles that contain digestive enzymes

Hydrolyse worn out organelles and pathogens

Question 15

Scanning Electron Microscope

Answer 15

Sample does not need to be thin
3D image
Lower resolution
Dead sample
Black and white image

Question 16

Quaternary Protein Structure

Answer 16

2 or more polypeptides joined together

Question 17

Transmission Electron Microscope

Answer 17

High resolution
High magnification
2D image
Dead sample
Thin sample
Black and white image

Question 18

How do pathogens cause disease?

Answer 18

Release toxins

Direct damage to cells

Question 19

Antibodies

Answer 19

Protein made in response to a foreign antigen.

Have binding sites specific to antigen

Question 20

Production of Monoclonal Antibodies

Answer 20

1. Inject mouse with disease to start immune response.
2. Isolate B cells and fuse with tumour cells
3. Antibodies isolated then cloned

Question 21

Vaccination

Answer 21

A dead, weakened or attenuated sample if a pathogen that initiate an immune response and the production of memory cells.

Question 22

Biuret Test

Answer 22

For proteins
1. Add sodium hydroxide solution
2.Add copper sulphate solution
colour change from clear blue to violet if protein present

Question 23

Emulsion Test

Answer 23

For lipids
1. Add ethanol
2. Add water
turns cloudy if lipids present

Question 24

Monosaccharides that make up carbohydrates are…

Answer 24

Glucose
Fructose
Galactose

Question 25

How are carbohydrates joined and what bond is formed?

Answer 25

Condensation reaction and glycosidic bond is formed.

Question 26

Benedict's Test

Answer 26

``` For reducing sugars 1. Boil sample with benedict's reagent 2. Coloured precipitate formed if reducing sugar present. Red ppte - much sugar Green ppte- small amount of sugar ```

Question 27

Test for Non Reducing sugars

Answer 27

1. Heat with dilute acid 2. Add sodium hydrogen carbonate to neutralise. 3. Test with benedicts as you would with reducing sugar, should give positive result

Question 28

Which parts of the body are most vulnerable to infection and why?

Answer 28

Gas exchange system and lining of the digestive system They are in contact with the environment at all times Have a large surface area Have a thin exchange surface.

Question 29

Risk factor

Answer 29

factors that increase the chance of developing a disease.

Question 30

Factors that increase the risk of cancer

Answer 30

Exposure to ionising radiation | Exposure of carcinogenic chemicals

Question 31

Factors that increase the risk of CHD

Answer 31

``` Lack of exercise High lipid diet Smoking High cholesterol diet Stress High blood pressure ```

Question 32

Percentage change

Answer 32

Change ------------ x 100 Original

Question 33

Describe question points

Answer 33

Say what you see Give an overall trend State any significant changes in data Use data from graph/table in answer

Question 34

Data handling question answers

Answer 34

Must be balanced | Give a reason why correlation may not show causation

Question 35

Stages of Protein Synthesis

Answer 35

``` Nucleus Ribosomes Rough Endoplasmic Reticulum Golgi Vesicles ```

Question 36

How to calculate magnification

Answer 36

``` Image size ---------------- Object size Always measure in mm Convert answer into micrometers ( x1000) ```

Question 37

Stages of phagocytosis

Answer 37

1. Phagocyte follows chemoattracants released by pathogen. 2. Phagocyte engulfs pathogen. 3. Pathogen enclosed in vesicle. 4. Lysosome fuses with vesicle and releases digestive enzymes that hydrolyse pathogen. 5. Waste material ejected from cell.

Question 38

Cellular response to infection

Answer 38

1. Antigen presents pathogen antigens on cell surface after phagocytosis. 2. T cell binds to antigen. 3. t cell activated and clones to help fight infection.

Question 39

Humoral response to infection

Answer 39

1. T cell binds to presented antigen and activates B cell. 2. T cell releases chemicals that signal to the B cell to clone into plasma cells and Memory cells by mitosis. 3. Plasma cells produce antibodies 4. Memory cells remain in the body to fight future re- infections.

Question 40

Secondary Response

Answer 40

Memory cells producing antibodies to fight a re-infecton of a disease. More antibodies are produced more quickly.

Question 41

Antigenic Variability

Answer 41

Some pathogens have antigens that mutate and change shape e.g. influenza making it more difficult to produce a vaccine for that disease because the pathogen will not be recognised by memory cells.

Question 42

What is passive immunity

Answer 42

Antibodies are received from elsewhere i.e. are not produced by an individual. Can be given by mother or an injection.

Question 43

What is active immunity

Answer 43

Immunity provided by memory cells produced by a primary response to a pathogen.

Question 44

What is a disadvantage of using an attenuated vaccine?

Answer 44

Vaccine may mutate into full version of virus and patient may need to fight a full infection

Question 45

Herd Immunity

Answer 45

Lots of individuals are vaccinated so there is little chance of the disease spreading because there is a low chance that non vaccinated people will come into contact with the disease.

Question 46

Immune response mark points

Answer 46

1. Vaccine contains sample of pathogen. 2. Phagocyte hydrolyses pathogen and presents antigens. 3. T cell binds to antigen. 4. T cell activates B cell 5. B cell divides into plasma and memory cells. 6. Vaccine stimulates primary response. 7. Memory cells produced give rapid response to future re infections.

Question 47

Why antibodies target and bind to only one antigen?

Answer 47

Complementary and specifically shaped binding site. | Antigen - antibody complex formed.

Question 48

What chemical elements do all protein and amino acids contain?

Answer 48

Carbon, Hydrogen, Oxygen, Nitrogen

Question 49

What are names and formulae of the two groups in the general structure of an amino acid?

Answer 49

Amino group - NH2 | Carboxylic Acid group - COOH

Question 50

What molecules are formed in a condensation reaction between two amino acids?

Answer 50

Dipeptide molecule and water

Question 51

Explain how a change in the primary structure of a protein may result in a different 3 dimensional structure.

Answer 51

1. change in primary structure leads to a change in the sequence of amino acids. 2. Therefore change in secondary structure and change in the position of bonds between R groups in tertiary structure. 3, Change in position of hydrogen, ionic and disulphide bonds so change in 3D structure.