B1

Question 1

What does the nucleus do?

Answer 1

Controls activities of the cell
Contains organism’s genetic material
Determines cell’s appearance and function
Contains instructions to make new cells or organisms

Question 2

What does the mitochondria do?

Answer 2

Where respiration happens
Enzymes enable glucose and oxygen to react together to transfer viral energy to the organism

Question 3

What is the cell membrane?

Answer 3

A barrier that controls which substances enter and leave the cell

Question 4

What is the cell wall?

Answer 4

It surrounds the cell and is made of cellulose
Makes the wall rigid and supports the cell

Question 5

What is the chloroplast?

Answer 5

Contains green chlorophyll
This transfers energy from the sun to the plant which is used in photosynthesis
Chloroplasts are only in the green parts of the cell

Question 6

What is the vacuole?

Answer 6

Full of cell sap
Water solution of sugar and salts
Helps keep the cell rigid
Supports the plant and keeping it upright

Question 7

What does an animal cell contain?

Answer 7

Nucleus
Mitochondria
Cytoplasm
Cell membrane

Question 8

What does a plant cell contain?

Answer 8

Everything is an animal cell as well as
Vacuole
Cell wall
Chloroplasts

Question 9

What does a prokaryotic cell contain?

Answer 9

Cell wall
Genetic material
Cytoplasm
Cell membrane
A bacterial chromosome which is usually circular

Question 10

What features do bacterial cells contain?

Answer 10

Flagella
Pili
Slime capsule
Plasmid

Question 11

What is the flagella and what does it do?

Answer 11

‘Tail-like’ structures that allow the cell to move through liquids

Question 12

What are pili and what do they do?

Answer 12

Tiny ‘hairlike’ structures that enable the cell to attach to structures
Also used to transfer genetic material between bacteria.

Question 13

What is the slime capsule and what does it do?

Answer 13

Layer outside the cell wall
Protects bacterium from drying out and from poisonous substances
Helps bacteria stick to smooth substances

Question 14

What is a plasmid and what does it do?

Answer 14

A circular piece of DNA that is used to store extra genes
Those genes are not needed for the bacterium’s survival but may help in times of stress
As an example, this is where antibiotic resistance genes are normally found

Question 15

What is the equation for total magnification?

Answer 15

Eyepiece lens magnification x objective lens magnification

Question 16

What is used to identify the nucleus of an animal cell?

Answer 16

Methylene blue

Question 17

What is used to identify the nucleus of a plant cell?

Answer 17

Iodine solution

Question 18

What is used to identify bacterial wall cells?

Answer 18

Crystal violet and it stains them

Question 19

What does a light microscope contain?

Answer 19

Eyepiece lens
Objective lens
Coarse focus
Fine focus
Stage
Slide
Light/mirror

Question 20

What are the two types of electron microscopy?

Answer 20

Transmission electron microscopes (TEM)
Scanning electron microscope (SEM)

Question 21

What does a TEM do?

Answer 21

Produce the most magnified image
Uses a beam of electrons to pass through a thin slice of the sample producing a 2D image

Question 22

What does an SEM do?

Answer 22

Produces a 3D imagine of a surface
They send a beam of electrons across the surface of a specimen. The reflected electrons are collected to produce an image

Question 23

What does an electron microscope contain from top to bottom?

Answer 23

Electron source
Electron beam
Specimen
Electromagnetic lenses
Viewing screen

Question 24

What are the advantages and disadvantages of a light microscope?

Answer 24

Cheap to buy and operate
Small and portable
Simpler to prepare a sample
Natural colour is seen (unless staining is used)
Specimens can be alive or dead

Question 25

What are the advantages and disadvantages of an electron microscope?

Answer 25

Expensive to buy and operate Large and more difficult to move Sample preparation is complex Black and white images produced Specimens have to be dead Better magnification that an electron microscope

Question 26

What is a chromosome?

Answer 26

A molecule of DNA

Question 27

How many chromosomes do most people have in each of their cells?

Answer 27

46

Question 28

What are genes?

Answer 28

DNA is arranged into sections; SHORT SECTIONS OF DNA THAT CODE FOR A CHARACTERISTIC , such as eye colour are called genes.

Question 29

What do genes determine?

Answer 29

Blood group Whether you have freckles or dimples And more

Question 30

What does a DNA molecule look like?

Answer 30

And circular phosphate bonded to a triangular deoxy-ribose sugar bonded to a rectangular base

Question 31

What are the bases?

Answer 31

Adenine Thymine Guanine Cytosine

Question 32

What bases bond with what?

Answer 32

Adenine to Thymine Guanine to Cytosine

Question 33

What is transcription?

Answer 33

The DNA around a gene unzips so that strands are separated and one of these strands act as a template. Complimentary bases attache to the strand being copied which forms mRNA. There is no Thymine so Uracil is used instead.

Question 34

How are proteins made?

Answer 34

By a process called translation

Question 35

What is translation?

Answer 35

The mRNA made from transcription attaches to a ribosome. Here, the nucleotide is interpreted and a new protein is made: 1. The ribosome ‘reads’ the nucleotides on the mRNA in groups of three (base triplets or codons and each triplet codes for a specific amino acid) 2. The ribosome continues to read the triplet code, adding more and more amino acids. 3. The amino acids join together in a chain and that is called a protein.

Question 36

What is an enzyme?

Answer 36

A protein that is also a biological catalyst

Question 37

What do enzymes look like?

Answer 37

The are long chains of amino acids that are folded together to form a specific shape

Question 38

Do enzymes bind to all molecules?

Answer 38

No as they are highly specific with their enzyme substrate complex

Question 39

What is the lock and key hypothesis?

Answer 39

An enzyme is like a lock and a substrate is like a key and only a certain key can fit the lock meaning only a certain substrate can bind with a a certain enzyme

Question 40

What factors affect enzymes?

Answer 40

Temperature and pH and the concentrations of the enzyme and substrate

Question 41

What are the best conditions called for an enzyme?

Answer 41

Optimum conditions

Question 42

How do enzymes become denatured?

Answer 42

If the temperature is too hot

Question 43

What enzyme breaks down protein?

Answer 43

Protease

Question 44

What enzyme breaks down lipids?

Answer 44

Lipase

Question 45

What enzymes breaks down carbohydrates?

Answer 45

Carbohydrase

Question 46

What is the word equation for aerobic respiration?

Answer 46

Glucose + oxygen — carbon dioxide + water

Question 47

What is the symbol equation for aerobic respiration?

Answer 47

C6H12O6 + 6O2 — 6CO2+ 6H20

Question 48

What is aerobic respiration?

Answer 48

Respiration that uses oxygen

Question 49

What is the word equation for anaerobic respiration in plant?

Answer 49

Glucose - Ethanol + Carbon Dioxide

Question 50

What is the symbol equation for anaerobic respiration?

Answer 50

C6H12O6 — 2C5H5OH + 2CO2

Question 51

What is the equation for anaerobic respiration in humans?

Answer 51

Glucose — lactic acid

Question 52

What are the downsides of anaerobic respiration?

Answer 52

Lactic acid build up in your muscles, which causes pain and stops the muscles from contracting (fatigue)

Question 53

Why do you breath heavily after exercising?

Answer 53

To get extra oxygen to react with the lactic acid and break it down and the oxygen needed for this process is called the oxygen debt.

Question 54

What is the equation for the rate of photosynthesis?

Answer 54

1/time

Question 55

Where does photosynthesis occur?

Answer 55

Inside the plant’s chloroplast as they contain chlorophyll

Question 56

What is the word equation for photosynthesis?

Answer 56

Carbon dioxide + water — glucose + oxygen

Question 57

What is the symbol equation for photosynthesis?

Answer 57

6CO2 + 6H20 — C6H120 + 602

Question 58

What is the law for relative light intensity?

Answer 58

The inverse square law

Question 59

What is the formula for relative light intensity?

Answer 59

1/(distance from light source)^2

Question 60

How does light intensity affect the rate of photosynthesis?

Answer 60

The higher the light intensity the faster the rate of photosynthesis until photosynthesis reaches its maximum rate

Question 61

How does carbon dioxide affect the rate of photosynthesis?

Answer 61

The greater the carbon dioxide concentration, the faster the rate if reaction

Question 62

Why is carbon dioxide the most common limiting factor of photosynthesis?

Answer 62

The atmosphere only contains about 0.04% carbon dioxide

Question 63

Why do farmers use greenhouses?

Answer 63

To artificially increase the level of CO2 which increases photosynthesis.

Question 64

How does temperature affect the rate of photosynthesis?

Answer 64

The higher the temperature, the higher the rate of photosynthesis untilthe temperature increases too high and the enzymes denature

Question 65

What factors can we change to see their effect on the rate of photosynthesis?

Answer 65

Light intensity (place light sources at different distances) CO2 concentration (add potassium hydrogen carbonate to the water) Temperature (place apparatus in water baths at different temperature)