B1: Cell Structure And Transport

Question 1

Function of the nucleus

Answer 1

Contains genetic material
Controls the activities of the cell

Question 2

Cytoplasm

Answer 2

Most chemical processes happen here, controlled by enzymes

Question 3

Cell membrane

Answer 3

Controls the movement of substances in and out of the cell

Question 4

Mitochondria

Answer 4

Most energy is released by respiration here

Question 5

Ribosomes

Answer 5

Protein synthesis happens here

Question 6

Cell wall

Answer 6

Protects and strengthens the cell
Keeps its rigid structure

Question 7

Chloroplasts

Answer 7

Contain chlorophyll to absorb light energy for photosynthesis

Question 8

Permanent vacuole

Answer 8

Contains cell sap to keep cell turgid

Question 9

Eukaryotic Cell Features

Answer 9

Always part of plant and animal cells
Larger than prokaryotic cells (10 - 100 micrometers)
Genetic material enclosed in a nucleus

Question 10

Prokaryotic cell features

Answer 10

Always bacterial cells
Smaller than eukaryotic cells (0.1 - 5 micrometers)
Genetic material stored in small DNA loops called plasmids

Question 11

Electron microscope features

Answer 11

High magnification (x1,000,000)
High resolution (0.2 micrometers/200 nanometers)
Expensive
Take up lots of space

Question 12

Light microscope features

Answer 12

Low magnification (x400)
Low resolution (0.4 - 0.7 micrometers/400 - 700 nanometers)
Cheap
Easy to use

Question 13

Nerve cell adaptations

Answer 13

Carry electrical impulses around the body of an animal for rapid communication
Long axons to carry information
Synapses to pass information to other cells
Lots of dendrites to make connections with other cells
Lots of mitochondria for energy

Question 14

Sperm cell adaptations

Answer 14

Streamlines shape
Large nucleus containing lots of genetic material
Lots of mitochondria for energy
Has an acrosome containing enzymes to break through the egg for fertilisation

Question 15

Muscle cell adaptations

Answer 15

Contract and relax to bring about movement
Store glycogen to be used in respiration
Contain lots of mitochondria to transfer energy for contracting and relaxing
Contain proteins that slide over one another

Question 16

Root hair cell adaptations

Answer 16

Lots of mitochondria to transfer energy for active transport of mineral ions
Large permanent vacuole speeds up movement of water by osmosis
Large surface area for water to enter the cell

Question 17

Palisade Cell Adaptations

Answer 17

Carries out photosynthesis
Permanent vacuole keeps cell rigid, leaf spread and stem supported
Contains chlorophyll filled chloroplasts to absorb maximum light energy
Regular shape so cells can be packed closely together

Question 18

Phloem cell adaptations

Answer 18

Cell walls between cells break down to form sieve plates
Very few supporting structures
Supported by companion cells
Mitochondria of phloem provide energy to other cells

Question 19

Xylem cell adaptations

Answer 19

Spirals and rings of lignin to make them very strong
Cells can die and form hollow tubes

Question 20

Function of the phloem

Answer 20

Transports food around the plant

Question 21

Function of the xylem

Answer 21

Transports water around the plant

Question 22

Osmosis definition

Answer 22

Osmosis is the movement of water from a dilute Regino to a concentrated region across a partially permeable membrane (ppm)

Question 23

Active transport definition

Answer 23

The movement of substances from a dilute area to a concentrated area against the concentration gradient, using energy

Question 24

Diffusion definition

Answer 24

Diffusion is the movement of particles from an area of high concentration to low concentration until evenly spread