B1.2/3/4/5 - Specialised Cells/ eukaryote,prokaryotes.

Question 1

Nucleus

Answer 1

• controls all cellular activity
• surrounded by nuclear membrane
• contains genetic material need to produce proteins used to reproduce
• average diameter = 10micrometres

Question 2

Cytoplasm

Answer 2

• jelly like substance where aka organelles are suspended

- where most chemical reactions happen

Question 3

Cell membrane

Answer 3

• controls the passage of substances (glucose +mineral ions) which enter the cell
• controls movement of substances which leave the cell (urea + hormones)

Question 4

Mitochondria

Answer 4

• structured in the cytoplasm

- where aerobic respiration happens

Question 5

Ribosomes

Answer 5

• protein synthesis take place
• makes all proteins needed for cell
• suspended in cytoplasm

Question 6

Cell wall

Answer 6

• made of cellulose

- strengthens and supports cell

Question 7

Chloroplasts

Answer 7

• found in all green parts of cell
• chlorophyll makes them green
• chlorophyll absorbs light for photosynthesis

Question 8

Vacuole

Answer 8

• A space in the cytoplasm which contains cell sap

- keeps cell rigid to support it

Question 9

Large permanent vacuole indicates

Answer 9

• indicates role in osmosis

- indicates plant cell

Question 10

Chloroplasts

Answer 10

-indicates photosynthetic cell

Question 11

Sieve plates

Answer 11

-indicates transport of dissolved food

Question 12

Lignin for xylem cells indicate

Answer 12

-support for the transport of water

Question 13

Mitochondria indicates

Answer 13

-active movement cell

Question 14

Eukaryotic Cells

Answer 14

• have a definite nucleus
• have cell membrane, cytoplasms, dna inside nucleus
• eg animal/plant cells, fungi, Protista

Question 15

Prokaryotes

Answer 15

• have no true nucleus
• dna is stored in single strands of in additional plasmids
• eg bacterial chromosome have one dna loop free in the cytoplasm

Question 16

Plasmids

Answer 16

-used in stressful situations
-contains extra dna
-have special features that help with resistance
E.g antibiotic resistance

Question 17

Slime capsule

Answer 17

Found around the outside of cell wall

-prevents cell from dehydration

Question 18

Flagellum

Answer 18

• long protein strand

- lashes about allowing movement for the cell

Question 19

Red blood cell:

• function
• structure
• adaptations

Answer 19

• function = carry blood around body
• structure= haemoglobin, biconcave shape, no nucleus, flexible
• adaptations:
• haemoglobin = red pigment which oxygen binds to
• biconcave shape = large surface area to carry oxygen
• no nucleus = more space for oxygen
• flexible = so blood can squeeze through capillaries

Question 20

Nerve cells:

• function
• structure
• adaptations

Answer 20

• function = carry electric impulses around the body
• structure = lots of dendrites, an axon, synapses
• adaptations:
• make connections to other nerve cells
• carries nerve impulses
• chemical gap between cells that have lots of mitochondria = create special transmitter chemicals

Question 21

Muscle cell:

• function
• structure
• adaptations

Answer 21

• function = create tissue to assist movement of the body
• structure: special proteins, mitochondria, store glycogen
• adaptations:
• slide over each other making fibres contract
• transfer energy needed for chemical reactions to take place when contracting/relaxing
• broken down + used in cellular respiration for the fibres to contract

Question 22

Egg cells:

• function
• structure
• adaptations

Answer 22

• Function = carry female dna + create right environment for fertilisation
• Structures: nucleus, cytoplasm, cell membrane
• contains half female chromosomes
• increases surface area to allow more nutrients to be stored/allow growth
• changes after fertilisation so that no sperm may enter

Question 23

Sperm cell:

• function
• structure
• adaptations

Answer 23

• function: carry make dna + fertilise egg
• structure: flagellum, middle sections, acrosome, large nucleus
• allows movement of cell
• full of mitochondria to make energy
• contains enzymes used to break outer layer of egg
• contains all male dna to be passed on

Question 24

Root hair cell:

• function
• structure
• adaptations

Answer 24

• function: absorb water/minerals ions to be moved up cell via active transport
• structure: large surface area, permanent vacuole, many mitochondria
• absorbs more water
• speeds up active transport of water by osmosis form soil across cell
• transfer energy needed for active transport of mineral ions to cell

Question 25

Photosynthetic cell:

• function
• structure
• adaptations

Answer 25

• function= produce own food via photosynthesis
• structure = chloroplasts, arranged in continuous layers on the outer leaf/stem, permanent vacuole
• trap light needed for photosynthesis
• to absorb as much light as possible
• keeps cell rigid as a result of osmosis to support the stem and spread leaf out to trap more light

Question 26

Phloem Cells

• function
• structure
• adaptations

Answer 26

• function: living cells that transport food
• structure: cell wall/sieve plates, have companion cells
• break down into sieve plates to allow dissolved food to move freely round tubes
• help to keep cells alive by transferring their energy to move food around

Question 27

Xylem cells:

• function
• structure
• adaptations

Answer 27

• function = dead cells that transport water
• structures = cells die to form hollow tubes, rings of lignin
• allow water to move up/down
• make cells very strong and help withstand water pressure, support stem of plant