B1 - Cell biology

Question 1

Nucleus

Answer 1

Controls the activities of the cell

Contains DNA

Question 2

Cytoplasm

Answer 2

Liquid gel
Organelles are suspended in it
Reactions take place

Question 3

Cell membrane

Answer 3

Controls passage of substances like glucose and mineral ions into the cell
Controls urea and hormones going out

Question 4

Mitochondria

Answer 4

Aerobic respiration happens here

Question 5

Nerve cell function

Answer 5

Transmit electrical signals to allow the body to respond quickly to changes in its environment

Question 6

Nerve cell adaptations

Answer 6

Myelin sheath covers the axon
They are long so less cells are needed to carry electricity a certain distance
Dendrites allow the neuron to detect information from various receptor cells

Question 7

Red blood cell function

Answer 7

Transport oxygen around the body

Question 8

Red blood cell adaptations

Answer 8

Bioconcave disk shape increases surface area
No nucleus for extra space
Contain haemoglobin, which binds to oxygen

Question 9

Sperm cell function

Answer 9

Transport genetic material to the ovum during reproduction

Question 10

Sperm cell adaptations

Answer 10

Tail allows it to move
High number of mitochondria for moving energy
Enzymes assist entry into ovum

Question 11

Ciliated cell function

Answer 11

Removes mucus

Question 12

Ciliated cell adaptations

Answer 12

Flagella (tiny hairs) cover one side of the cell, allowing it to move mucus

Question 13

Muscle cell function

Answer 13

Contracts to allow movement

Question 14

Muscle cell adaptations

Answer 14

Contains fibres that can slide over each other to allow the muscle to contract

Question 15

Palisade cell function

Answer 15

Collect sunlight for photosynthesis

Question 16

Palisade cell adaptations

Answer 16

High number of chloroplasts

Rectangular shape allows cells to be tightly packed together

Question 17

Meristem cell
(definition and locations)

Answer 17

An unspecialised cell in a plant
Locations:
Buds - shoot tip meristems
Stem - so it can get thicker
Root tip - so roots can grow

Question 18

Stem cell

Answer 18

Unspecialised cell in animals

Question 19

Prokaryotes

5 features

Answer 19

Oldest cell type
Asexual reproduction
No nucleus
Single-celled
No organelles

Question 20

Eukaryotes

5 features

Answer 20

Evolved from prokaryotes
Larger and more complex than prokaryotes
Contain nucleus
Asexual or sexual reproduction
Contain organelles

Question 21

Plant cell

size in um

Answer 21

100um

Question 22

Animal cell

size in um

Answer 22

10um

Question 23

Bacteria

size in um

Answer 23

1um

Question 24

Virus

size in nm

Answer 24

50-100nm

Question 25

Real size =

complete equation

Answer 25

Real size = image size / magnification

Question 26

Light microscope

magnification

Answer 26

x2,000

Question 27

Electron microscope

magnification

Answer 27

x2,000,000

Question 28

Electron microscope

disadvantages

Answer 28

Very large
Very expensive
Require specific temperature, pressure and humidity

Question 29

1 metre is equal to…

cm, mm, um, nm

Answer 29

100cm (centimetres)
1,000mm (millimetres)
1,000,000um (micrometres)
1,000,000,000nm (nanometres)

Question 30

Electron microscope

how it works

Answer 30

A beam of electrons is sent at the thing being observed

The speed and position of the electrons as they bounce back is used to form an image

Question 31

Transmission electron microscope

Answer 31

2D with high magnification and resolution

Question 32

Scanning electron microscope

Answer 32

3D with lower magnification

Question 33

Magnification

Answer 33

How many times bigger and object looks than its actual size

Question 34

Resolution

Answer 34

The ability to distinguish between two points on an image

Question 35

Karyotype

Answer 35

The number and appearance of the chromosomes in the cell nuclei of an organism

Question 36

Autosome

Answer 36

Any chromosome that is not a sex chromosome