Topic 1 - Key Concepts In Biology

Question 1

What does a microscope do?

Answer 1

Makes small objects appear larger/magnifies small objects

Question 2

What part of a microscope do you look through?

Answer 2

eyepiece lens

Question 3

Which part of a microscope do you use to get a clear image?

Answer 3

the focusing wheel

Question 4

If an average height person in Year 10 is magnified 600 times, how tall will they be compared to the tallest building in the world, which is 828 m tall?

Answer 4

about the same height; the Burj Khalifa, Dubai is 828 m tall

Question 5

Put these in order of size, biggest first: atom, animal cell, cell nucleus, muscle tissue, protein molecule, water molecule

Answer 5

muscle tissue, animal cell, cell nucleus, protein molecule, water molecule, atom

Question 6

A microscope has a ×5 eyepiece lens and a ×5 objective lens. What is the total magnification?

Answer 6

25; 5 × 5 = 25

Question 7

A human hair has a width of 100 μm but appears 20 mm wide in a photo. What magnification is the photo?

Answer 7

×200; 20 mm = 20 000 μm; 20 000 ÷ 100 = 200

Question 8

How many millimetres are there in a metre?

Answer 8

1000

Question 9

What unit is 1000 times smaller than a millimetre?

Answer 9

micrometre, μm

Question 10

What is the unit symbol for a nanometre?

Answer 10

nm

Question 11

What is an estimation?

Answer 11

an approximate value

Question 12

Name one part you could find in a plant cell but not an animal cell.

Answer 12

cell wall, chloroplasts, permanent vacuole

Question 13

What process happens in a mitochondrion?

Answer 13

aerobic respiration

Question 14

What is one function of a plant cell’s permanent vacuole?

Answer 14

to help keep the cell rigid/to store substances

Question 15

In which part of a plant cell is cell sap stored?

Answer 15

vacuole

Question 16

In which part of a cell would you find chromosomes?

Answer 16

Nucleus

Question 17

When you look down a microscope, what is the area that you see called?

Answer 17

field of view

Question 18

Why can an electron microscope detect smaller structures in cells than a light microscope?

Answer 18

it has better magnification and better resolution

Question 19

What is a picture taken with a microscope called?

Answer 19

micrograph

Question 20

Some microscope pictures have a small line drawn on them with information about how long the line is when unmagnified. What is this line called?

Answer 20

scale bar

Question 21

List three sub-cellular structures that are usually found in animal cells.

Answer 21

any three from: cell membrane, nucleus, mitochondria,

Question 22

List three sub-cellular structures found in plant cells but not in animal cells.

Answer 22

large permanent vacuole, chloroplasts, cell wall

Question 23

Which cell structure controls what enters and leaves the cell?

Answer 23

cell membrane

Question 24

Which cell structure controls how the cell works?

Answer 24

nucleus

Question 25

In which cell structure does respiration mainly take place?

Answer 25

Mitochondria

Question 26

Which plant cell structure contains chlorophyll?

Answer 26

Chloroplast

Question 27

What is the function of the cell structure that contains chlorophyll?

Answer 27

to capture energy from light for photosynthesis/to produce glucose using photosynthesis

Question 28

Describe the function of the structure that surrounds plant cells, but not animal cells.

Answer 28

supports and protects the cell

Question 29

What is the function of ribosomes?

Answer 29

manufacture of proteins

Question 30

What are gametes?

Answer 30

Sex cells

Question 31

A bacterium is 20 μm long. How long is it in metres?

Answer 31

0.00002 m

Question 32

A bacterium is 5 μm wide. How wide is it in nanometres?

Answer 32

500 nm

Question 33

What part of an animal cell controls the cell’s activities?

Answer 33

Nucleus

Question 34

What do ribosomes make?

Answer 34

Proteins

Question 35

Name one part that a plant cell might have but an animal cell would not.

Answer 35

chloroplast, permanent large vacuole, cell wall

Question 36

What do bacteria use to move themselves?

Answer 36

flagella

Question 37

Animal and plant cells are eukaryotic. What word describes bacterial cells?

Answer 37

Prokaryotic

Question 38

Name one structure that an animal cell would have but a bacterial cell would not.

Answer 38

nucleus, mitochondria

Question 39

What is this format for numbers called: A × 10n?

Answer 39

Standard form

Question 40

What is 1 × 106 m written as an ordinary number?

Answer 40

1 000 000 m

Question 41

Name two substances that might be found in the cytoplasm of an egg cell to provide energy.

Answer 41

carbohydrate or starch, lipid or fat or oil

Question 42

Egg cells also contain protein. Which cell structure makes proteins?

Answer 42

ribosome

Question 43

In which system of the body is food broken down?

Answer 43

digestive system

Question 44

Why do we need to break food down?

Answer 44

because the molecules in food are too large to cross cell membranes

Question 45

In which organ of the body is digested food absorbed?

Answer 45

small intestine

Question 46

Which group of molecules help to digest food?

Answer 46

Enzymes

Question 47

Give one example of the group of molecules that you named in the previous question.

Answer 47

any suitable example, such as amylase, protease, lipase

Question 48

What does a sperm cell use enzymes for?

Answer 48

to digest a path through the jelly coat of the egg cell

Question 49

Do plants contain enzymes?

Answer 49

yes – they control many reactions inside plant cells | anywhere a reaction takes place

Question 50

Why are proteins and carbohydrates examples of polymers?

Answer 50

They are made up of many similar molecules/monomers.

Question 51

Which monomers make up starch?

Answer 51

Glucose

Question 52

Which monomers make up a protein?

Answer 52

amino acids

Question 53

Are enzymes carbohydrates, proteins or lipids?

Answer 53

proteins

Question 54

Which group of substances are fats and oils examples of?

Answer 54

lipids

Question 55

Name one food that contains a lot of starch.

Answer 55

any suitable example such as: potato, pasta, bread, rice

Question 56

What effect does the enzyme amylase have on starch?

Answer 56

breaks it down to small sugars/maltose

Question 57

Food provides nutrients for growth. What else is it a source of, which we need for activity?

Answer 57

energy

Question 58

Which cell structures break down molecules from food to release energy?

Answer 58

mitochondria

Question 59

What are the subunits (small molecules) that make up carbohydrates?

Answer 59

simple sugars, e.g. glucose

Question 60

Which two kinds of subunits form lipids (fats and oils)?

Answer 60

fatty acids and glycerol

Question 61

Which kind of large biological molecule are enzymes?

Answer 61

Proteins

Question 62

Which subunits make up enzymes?

Answer 62

Amino acids

Question 63

Amylase is a kind of enzyme. Where is it found in humans?

Answer 63

mouth/salivary glands and small intestine/pancreas

Question 64

What is a catalyst?

Answer 64

A molecule that speeds up the rate of a reaction

Question 65

Why are enzymes called biological catalysts?

Answer 65

They are molecules found inside living organisms that speed up the rate of reactions.

Question 66

What is a substrate?

Answer 66

A molecule that is changed in a reaction

Question 67

What is the substrate for amylase?

Answer 67

starch

Question 68

Starch synthase is an enzyme that catalyses the synthesis of starch. Explain what this means.

Answer 68

The enzyme combines with subunits/small sugar molecules and helps them join together to form starch.

Question 69

What are the subunits of enzymes?

Answer 69

amino acids

Question 70

Why do different enzymes have different 3D shapes?

Answer 70

The amino acids are arranged in a different order in different proteins.

Question 71

Which kind of large organic molecule does a protease digest?

Answer 71

proteins

Question 72

Which kind of enzyme would break down a food stain made by sunflower oil?

Answer 72

lipase

Question 73

What is the name of the part of an enzyme into which the substrate fits?

Answer 73

active site

Question 74

Why do most enzymes only work with one substrate?

Answer 74

Only substrates with the same shape as the active site can sit in the site and take part in the reaction.

Question 75

Enzymes are specific to their substrate. What does this mean?

Answer 75

The enzyme will only work with particular substrates – those substrates that have the right shape.

Question 76

Which term describes an enzyme in which the active site has permanently changed shape?

Answer 76

denatured

Question 77

What effect does a large change of shape of an enzyme's active site have on how the enzyme works?

Answer 77

The enzyme no longer works.

Question 78

Give two examples of changes in the cell environment that could cause the active site to change shape.

Answer 78

pH, temperature

Question 79

Which cell structure surrounds every kind of cell?

Answer 79

cell surface membrane

Question 80

What is the function of this cell structure?

Answer 80

to control what enters and leaves the cell

Question 81

Name one gas that a cell needs to take in from its surroundings, and explain your answer.

Answer 81

oxygen needed for respiration/to release energy in mitochondria; carbon dioxide needed for photosynthesis

Question 82

Name one other substance that a cell needs to take in from its surroundings, and explain your answer.

Answer 82

any suitable answer, such as glucose/sugar needed for respiration

Question 83

Carbon dioxide is produced inside a cell and moves out of the cell by diffusion. What does this mean?

Answer 83

there is an overall movement of gas particles from where there are more of them to where there are fewer

Question 84

Name one other substance that is made inside a cell and leaves the cell.

Answer 84

any suitable substance, such as enzymes or hormones that are secreted

Question 85

Name two substances that plants take in from the soil through their roots.

Answer 85

water and dissolved mineral salts

Question 86

There is a 5% sucrose solution and a 10% sucrose solution. Which solution has the higher concentration of sucrose?

Answer 86

10% solution

Question 87

Two beakers contain the same volume of solution. One is a 10% sodium chloride solution, the other is a 5% sodium chloride solution. Which beaker contains more water molecules?

Answer 87

5% solution