Specialised Cells

Question 1

Nerve Cell

Answer 1

Function:
transmits nervous stimuli
Adaption:
synapses and neurotransmitter
can be very long
myelin sheet (insulator)

Question 2

Ciliated Cell

Answer 2

Function:
e.g. clear airways
Adaption:
cilia that beat backwards and forwards to move material
e.g. sweep mucus with trapped dust and bacteria along the throat

Question 3

Sperm Cell

Answer 3

Function:
fertilisation of egg
Adaption:
small with tail for movement
lots of mitochondria
acrosome with enzymes to digest egg membrane
genetic information (23 chromosomes)

Question 4

Egg Cell

Answer 4

Function:
fertilisation
Adaption:
large and bulky 
contains yolk
genetic information (23 chromosomes)

Question 5

Red Blood Cell

Answer 5

Function:
transport of oxygen
Adaption:
contains haemoglobin which binds oxygen
no nucleus (more space for haemoglobin)
biconcave shape

Question 6

White Blood cell

Answer 6

Function:
destroy pathogens
Adaption:
some produce antibodies
some have flexible cytoskeleton so that they can change shape quickly to engulf bacteria

Question 7

Muscle Cell

Answer 7

Function:
contraction
Adaption:
long and flexible
lots of mitochondria

Question 8

Fat Cell

Answer 8

Function:
store fat (source of energy)
Adaption:
Little cytoplasm: lots of fat storage space
few mitochondria
can expand (up to 100x)

Question 9

Rods and Cones

Answer 9

Function:
photoreception - vision
Adaption:
contain visual pigment that detects light
many mitochondria
synapse that transmits signals to optic nerve

Question 10

Skin Cell

Answer 10

Function:
protection
heat regulation
Adaption:
pigment to absorb UV
hair for insulation

Question 11

Palisade Cell

Answer 11

Function:
photosynthesis
Adaption:
lots of chloroplasts
tightly packed, elongated

Question 12

Root Hair Cell

Answer 12

Function:
uptake of water and minerals
Adaption:
have root hairs (increases surface area)
large permanent surface
close to xylem (water transport)

Question 13

Guard Cell

Answer 13

Function:
control opening of stomata
Adaption:
take up and release water by osmosis to open and close stomata 
thickened cell wall

Question 14

Specialised Cell

Answer 14

a cell that can differentiate into a cell with a role (e.g. blood cell). It can turn DNA on or off. It is the only cell that goes through mitosis

Question 15

Describe the function of the mitochondria and suggest a reason why they are arranged in the filament near the tail of the sperm?

Answer 15

mitochondria release energy in respiration - the energy can quickly get to the tail where the energy is used for swimming

Question 16

Explain the contribution of the sperm nucleus in determining the characteristics of the off spring

Answer 16

DNA determines characteristics. 23 chromosomes containing genetic information are situated in the nucleus, they contribute to half the genetic make up