B1 Cell Structure And Transport

Question 1

Diffusion

Answer 1

The net movement of particles from an area of high concentration to an area of low concentration.

Question 2

Why does diffusion happen?

Answer 2

Due to the random movement of the particles, they bounce into each other and obstacles.

Question 3

How much energy is used in diffusion?

Answer 3

It is a passive process which means no energy is needed.

Question 4

Concentration gradient

Answer 4

The difference in concentration between two areas.

Question 5

Steep concentration gradient

Answer 5

Faster diffusion

Question 6

Shallow concentration gradient

Answer 6

Slower diffusion.

Question 7

Higher temperature

Answer 7

Faster diffusion as particles have more energy.

Question 8

Lower temperature

Answer 8

Slower diffusion.

Question 9

Large surface area

Answer 9

Faster diffusion.

Question 10

Small surface area

Answer 10

Slower diffusion.

Question 11

Osmosis

Answer 11

The movement of water from a dilute solution to a more concentrated solution.

Question 12

Partially permeable membrane

Answer 12

Membranes that only let some particles through them.

Question 13

Isotonic

Answer 13

Same

Question 14

Hypertonic

Answer 14

Higher

Question 15

Hypotonic

Answer 15

Lower

Question 16

Magnification =

Answer 16

Size of image / size of real object

Question 17

Resolution

Answer 17

The ability to distinguish between two seperate points

Question 18

Nucleus

Answer 18

Controls all the activities of the cell. Contains the genes on the chromosomes that carry the instructions for making the proteins needed to build new cells or new organisms

Question 19

Cytoplasm

Answer 19

A liquid gel in which the organelle are suspended and where most of the chemical reactions needed for life take place

Question 20

Cell membrane

Answer 20

Controls the passage of substances such as glucose and mineral ions into the cell. Also controls the movement of substances such as urea or hormones out of the cell

Question 21

Mitochondria

Answer 21

Structures in the cytoplasm where aerobic respiration takes place, releasing energy for the cell

Question 22

Ribosomes

Answer 22

Where protein synthesis takes place, making all the proteins needed in the cell

Question 23

Cell wall

Answer 23

Strengthens the cell and gives it support. Made of cellulose

Question 24

Chloroplasts

Answer 24

Contain the green substance chlorophyll which absorbs light so the plant can make food by photosynthesis

Question 25

Permanent vacuole

Answer 25

A space in the cytoplasm filled with cell sap. Keeps the cell rigid and helps to support the plant

Question 26

Eukaryotic cells

Answer 26

Cells that have a membrane, cytoplasm, and genetic material enclosed within a nucleus

Question 27

Prokaryotic cells

Answer 27

Cells which do not have a nucleus- the DNA is free in the cytoplasm

Question 28

Plasmids

Answer 28

Small rings of DNA found in some prokaryotic cells, which code for very specific features such as antibiotic resistance

Question 29

Flagella

Answer 29

Long protein strands that lash out and allow the bacteria to move

Question 30

Adaptations of nerve cells

Answer 30

Lots of dendrites to make connections to other nerve cells, an axon that carries the nerve impulse from one place to another, and the nerve endings are adapted to pass impulses using special transmitter chemicals (they contain lots of mitochondria to provide the energy needed to make the chemicals)

Question 31

Adaptations of striated muscle cells

Answer 31

Special proteins that slide of each other making the fibres contract, many mitochondria to transfer the energy needed for the chemical reactions that take place as the cells contract and relax, and they can contain glycogen (a chemical that can be broken down and used in cellular respiration by the mitochondria to transfer the energy needed for the fibres to contract)

Question 32

Adaptation of sperm cells

Answer 32

A long tail whips from side to side to help it move, the middle section is full of mitochondria which transfer the energy needed for the tail to work, the acrosome stores the digestive enzymes for breaking down the outer layers of the egg, and a large nucleus contains the genetic material to be passed on

Question 33

Adaptations of root hair cells

Answer 33

They greatly increase the surface area available for water to move into the cell, large permanent vacuole that speeds up movement of water by osmosis from the soil across the root hair cell, many mitochondria transfer the energy needed for the active transport of mineral ions into the cell

Question 34

Adaptations of photosynthetic cells

Answer 34

Chloroplasts contain chlorophyll, which traps the light needed for photosynthesis, usually positioned in the leaves and outer layers of the stem of a plant so they absorb more light, and have a large permanent vacuole which keeps the cells rigid as a result of osmosis

Question 35

Adaptations of xylem cells

Answer 35

Xylem cells are alive when first formed but the chemical lignin builds up in spirals in the cell walls and the cells die to form long hollow tubes, and the spirals or lignin make them very strong and help withstand the pressure of the water moving up

Question 36

Adaptations of phloem cells

Answer 36

Cells walls break down to form special sieve plates which allow water carrying dissolved food to move freely up and down. Phloem cells are supported by their companion cells that help keep them alive. The mitochondria of the companion cells transfer the energy needed

Question 37

Diffusion occurs down a…

Answer 37

Concentration gradient

Question 38

Plasmolysis

Answer 38

When too much water is lost from osmosis, the vacuole and cytoplasm shrink, and eventually the cell membrane pulls away from the cell wall

Question 39

Flaccid

Answer 39

Soft

Question 40

Turgid

Answer 40

Normal