Paper 1 A1

Question 1

3 polysaccharides

Answer 1

Starch Glycogen Cellulose

Question 1

Bond between glucose molecules

Answer 1

Glycosidic bond (1-6/1-4)

Question 2

Glucose + Glucose

Answer 2

Maltose +H2O

Question 3

Glucose + Fructose

Answer 3

sucrose + H2O

Question 4

Cell mediated response

Answer 4

Present antigens on cell surface membrane of a phagocyte
Complimentary T -helper cell binds to antigen
T-cell undergoes clonal expansion
T-helper cells, Cytotoxic T-killer cells and T- memory cells

Question 5

Humoral response

Answer 5

B-cell collides with complimentary antigen
B-cell engulfs antigen by endocytosis
B-cell binds to complimentary T -help cell
Activates B-cell, B-cell undergoes clonal expansion to B-memory-cells and plasma cells

Question 6

Phagocytosis

Answer 6

Phagocyte detects pathogen by chemotaxis
Phagocyte engulfs pathogen via endocytosis
Pathogen is engulfed within a phagosome
Vesicle fuses with phagosome and releases its contents
Hydrolysing enzymes (lytic enzymes) hydrolyses bonds within the pathogen
Soluble products of the pathogen are used, some are released by exocytosis

Question 7

B-memory cell

Answer 7

Cell that can differentiate into plasma cells

Question 8

plasma cell

Answer 8

Cell that produces antibodies

Question 9

Antibody structure

Answer 9

Light chain heavy chain, disulfide bridges, variable region and antigen binding site

Question 10

Cell surface membrane structure + function

Answer 10

Phospholipid bilayer
Cholesterol
Integral proteins
Channel proteins
Carrier proteins
controls what enters and exits the cell

Question 11

Nucleus
Structure + function

Answer 11

Contains genetic material of the cell
Nucleoplasm
Nucleolus
Site of transcription and DNA replication
contains chromosomes

Question 11

SER
structure + function

Answer 11

Folded membranes - cristernae
Stores and synthesises lipids and carbohydrates

Question 12

RER
structure + function

Answer 12

folded membranes - cristernae with ribosomes attached

Question 13

Golgi apparatus
structure + function

Answer 13

Folded membranes -cristernae
Secretory vesicles pinch off from the cristernae
Add carbohydrates to proteins forming glycoproteins
Secrete carbohydrates
transport modify and package the lipids
Form lysosomes
Molecules labelled with their destination
Finished products are transported to the cell surface membrane and the contents are removed

Question 13

Lysosomes
Structure and function

Answer 13

Bags of digestive enzymes Hydrolyse phagocytic cell
Completely break down dead cells (autolysis)
Exocytosis release enzymes to outside of the cell to destroy material
digest worn out organelles for the reuse if materials

Question 14

Mitochondria

Answer 14

Double membrane
Inner membrane called the cristae
Site of aerobic respiration
Site of ATP production
DNA to code for proteins used in respiration

Question 15

Ribosomes

Answer 15

Protein + rRNA
80s - Large ribosome (eukaryotic cells)
70s - smaller ribosome (prokaryotic, mitochondria and chloroplasts)
Site of protein synthesis

Question 16

Vacuole

Answer 16

Filled with fluid surrounded by a single membrane (tonoplast)
Cells become turgid and therefore provide support

Question 17

Homologous chromosomes

Answer 17

Two chromosomes that contain the same genes with possibly different alleles, one maternal chromosome and one paternal chromosome

Question 18

Chloroplasts

Answer 18

Surrounded by a double membrane
Stroma (thylakoid membranes)
Site of photosynthesis
contains ribosomes for making enzymes involved in respiration

Question 19

Cell wall

Answer 19

Plant - microfibrils

Question 20

viruses

Answer 20

Capsule, attachment protein, viral DNA

Question 21

Optical microscope

Answer 21

Colored, living, lower resolution and lower magnification

Question 22

TEM

Answer 22

Transmission electron microscope black and white non-living ( vacuum) higher resolution higher magnification

Question 23

SEM

Answer 23

scanning electron microscope non-living (vacuum) higher resolution higher magnification not thin electrons are scattered

Question 24

Magnification

Answer 24

How many times larger the image is compared the object

Question 25

Resolution

Answer 25

The minimum distance between the objects in which they can be viewed as separate

Question 26

Cell fractionation

Answer 26

Cells are broken open to release the contents and organelles are separated reducing enzymes Prepared in cold isotonic solution buffered solution

Question 27

Homogenization

Question 28

Mitosis

Answer 28

PMAT

Question 29

Binary fission

Answer 29

Replication of DNA and plasmids Division of cytoplasm to produce two daughter cells Single copy of the circular DNA and variable number of plasmids

Question 30

Antigen

Answer 30

Molecules that create an immune response by lymphocytes that are detected in the body

Question 31

Antibody

Answer 31

A protein that is found in the blood produced by plasma cells

Question 32

1st stage of protein synthesis

Answer 32

transcription

Question 33

2nd stage of protein synthesis

Answer 33

translation

Question 34

Transcription

Question 35

Transcription

Answer 35

DNA molecule is unzipped by the action of DNA helicase free nucleotides align up by complimentary base pairings joined by RNA polymerase forming phosphodiester bonds

Question 36

tRNA structure and function

Answer 36

clover leaf shaped polypeptide chain held together by hydrogen bonds amino acid binding site and anticodon

Question 37

mRNA structure and function

Answer 37

complimentary base strand single stranded molecule binds to ribosome in order to create a new polypeptide chain through protein synthesis

Question 38

DNA replication

Answer 38

DNA Helices breaks the hydrogen bonds between complimentary base pairs Unzipping the double helix separating strands only one strand acts as a template Free nucleotides line up RNA polymerase joins complimentary freenucleotides via condensation reactions forming phosphodiester bonds between adjacent nucleotides

Question 39

Lipid digestion

Answer 39

physical + chemical Bile salts immulsify lipids forming micelles, increasing the surface area for lipase to act on

Question 40

Micelles

Answer 40

Vesicles formed from fatty acids, glycerol, monoglycerides and fatty acids

Question 41

Bohr shift

Answer 41

Oxygen partial pressure decreases with pH as carbonic acid increases H+ conc causing haemolglobin to disassociate its oxygens

Question 42

Cardiac output

Answer 42

Stroke volume x heart rate

Question 43

Tissue fluid

Answer 43

Fluid containing water, glucose, amino acid, fatty acids, ions and oxygen which bathes the tissues

Question 44

Ultrafiltration

Answer 44

The process of which a pressure gradient is created through the contraction of the left ventricle forcing tissue fluid out of the capillaries

Question 45

Mass flow hypothesis

Answer 45

H+ ions are actively pumped from the companion cell into the sieve tube elements causing sucrose to move into the sieve tube elements through co transport decreasing the water potential of the sieve tube element causing water to move into the sieve tube element through osmosis creating a hydrostatic pressure gradient moving sucrose from the source cells into the sink cells through facilitated diffusion

Question 46

Transpiration

Answer 46

Water leaves through the stomata and enters through the roots evaporation osmosis

Question 47

Facillitated diffusion

Answer 47

Diffusion that involves the energy from the hydrolysis of ATP

Question 48

How does the size of an organism relate to its surface area to volume ratio

Answer 48

The larger the organism the smaller its surface area to volume ratio