cell specialisation and differentiation

Question 1

2 ways xylem cells are adapted so water can flow through them

Answer 1

1. they form continuous, hollow tubes with no ends, that have very few subcellular structures to provide a continuous route for water to flow
2. their cell walls become strengthened by lignin which gives support and helps the tubes withstand the water pressure

Question 2

2 ways phloem cells are adapted to transport nutrients and sugars

Answer 2

1. form long tubes but have end walls with pores so that cell sap can move between cells
2. companion cells provide energy needed for active transport

Question 3

3 ways root hair cells are specialised for absorbing water and minerals

Answer 3

1. they grow into long hairs which stick out into the soil which gives the plant a big surface area for absorption
2. contain lots of mitochondria to provide energy for active transport
3. thin walls that don’t restrict water consumption

Question 4

4 ways sperm cells are specialised for reproduction

Answer 4

1. long tail (flagellum) and a streamlined head to help swim to egg
2. lots of mitochondria to provide energy needed
3. carries enzymes in head to digest through egg cell membrane
4. haploid nucleus contains genetic information

Question 5

3 ways nerve cells are specialised for rapid signalling

Answer 5

1. cells are long (long axon) to cover more distance, allows electrical impulses to be transmitted all over the body
2. have branched connections (dendrites) to connect to other nerve cells and form a network
3. myelin sheath speeds up transmission of impulses along the cell

Question 6

3 ways muscle cells are specialised for contraction

Answer 6

1. cells are long so they have space to contract
2. contain lots of mitochondria to generate energy
3. arrangement of protein filaments allows cells to slide over each other to produce muscle contraction

Question 7

function of a sperm cell

Answer 7

to get the male DNA to the female DNA

Question 8

function of a nerve cell

Answer 8

to carry electrical signals from one part of the body to another

Question 9

function of a muscle cell

Answer 9

to contract quickly

Question 10

function of a root hair cell

Answer 10

to absorb water and minerals

Question 11

function of phloem cell

Answer 11

transport substances around plant

Question 12

function of a xylem cell

Answer 12

transport water from roots to leaves in a plant

Question 13

cell differentiation

Answer 13

the process by which a cell changes to become specialised for its function

Question 14

when does most differentiation occur?

Answer 14

as an organism develops, during early foetal stage

Question 15

when is the ability to differentiate lost in plant and animal cells?

Answer 15

animal-lost at an early stage
plant-never lose ability

Question 16

why is cell differentiation important?

Answer 16

allows production of different tissues and organs that perform vital functions

Question 17

what changes does a cell go through as it differentiates?

Answer 17

acquires different sub-cellular structures to enable a specific function to be performed