How Are Certain Cells Specialised

Question 1

Erythrocytes function & structure

Answer 1

can carry oxygen around the body
No nucleus + few organelles -> maximised Hb & so O2 that is carried
Biconcave disk shape -> increase rate of diffusion of oxygen in & out of cells
Flexible shape (elastic membrane + complex cytoskeleton) + small -> can squeeze through narrow capillaries

Question 2

Neutrophils function & structure

Answer 2

destroy pathogens by phagocytosis
Multilobed nucleus & flexible shape -> can squeeze through gaps in capillary walls
Many lysosomes / digestive enzymes -> helps digest & destroy foreign bodies

Question 3

Ciliated epithelial cells in airways function & structure

Answer 3

move mucus along the surface of tissue
E.g. cilia -> sweep mucus along the surface of tissue to the top of the airway
E.g. goblet cell -> secrete mucus

Question 4

function & structure if squamous epithelial cells

Answer 4

1 cell thick and permeable
Reduces / easy diffusion distance for CO2 & O2

Question 5

Sperm cells function & structure

Answer 5

fuse w/ ovum during fertilisation, so the embryo can develop
Acrosome = digestive enzymes in it -> breaks down eggs protective outer layer so nuclei can fuse
Tail -> rotates to propel cell forward + allows movement towards egg
Many mitochondria in mid piece -> release energy via aerobic respiration for movement
Streamlined shape -> reduces resistant during movement

Question 6

function & structure of root hair cells

Answer 6

absorb water & mineral ions from soil
Root hair = increases surface area to increase rate of water uptake & ions taken in
Mitochondria = releases energy via aerobic respiration for active transport of ions
Permanent vacuole = contains cell sap + maintains w.p. gradient

Question 7

Palisade cells function & structure

Answer 7

carry out photosynthesis

Many chloroplasts near edge of cells = maximise absorption of light for photosynthesis & reduce diffusion distance for carbon dioxide
Tall & thin shape = deeper penetration of light as many cells can be packed together

Question 8

Guard cells function & structure

Answer 8

One side of wall thicker than the other -> allows the cell to bend & change shape
Many mitochondria -> releases energy (maximum)