cell differentiation and specialisation

Question 1

differentiation

Answer 1

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

Question 2

as cells change…

Answer 2

they develop different subcellular structures and turn into different types of cells.

Question 3

when does most differentiation occur

Answer 3

as the organism develops. in most animals, the ability is lost after they become specialised, in an early stage

most plant cells never loose this ability

Question 4

stem cells

Answer 4

undifferentiated cells

Question 5

examples of specialised cells

Answer 5

• sperm cells specialised for reproduction
• nerve cells specialised for rapid signalling
• muscle cells specialised for contraction
• root hair cells specialised for water & minerals
• phloem & xylem cells specialised for transporting
  substances

Question 6

sperm cell specialisation

Answer 6

function = to get male DNA to the female DNA
- long tail & streamlined head for swimming
- lots of mitochondria to provide energy
- enzymes in its head to digest through egg cell
membrane

Question 7

nerve cell specialisation

Answer 7

function = to carry electrical signals around the body
- long cells to cover more distance
- branched connections at the ends to connect to
other nerve cells and from a network across the
body

Question 8

muscle cell specialisation

Answer 8

function = to contract quickly
- long cells so they have space to contract
- lots of mitochondria to generate energy needed for
contraction

Question 9

root hair cell specialisation

Answer 9

function = absorb minerals and water
- big surface area for absorbing
- hairs stick out into soil for a big surface area

Question 10

phloem & xylem cell specialisation

Answer 10

function = transport substances eg. food and water
- cells are long and joined end to end to form tubes
- xylem are hollow in the centre so stuff can flow
through
- phloem have very few subcellular structures so
stuff can flow through