cell diversity 2.6

Question 1

Features of Palisade cells

Answer 1

Pack together quite closely w small spaces between them for air to circulate
Large vacuole so chloroplasts are positioned nearer periphery of cell
Contain many chloroplasts
Cytoskeleton threads and motor proteins move many chloroplasts to upper surface of leaf when light intensity is high

Question 2

Features of guard cells

Answer 2

Light energy used to make ATP
ATP actively transports potassium ions into guard cells
Water potential lowered, so water moves in by osmosis
Guard cells swell at tips, tips bulge
Forms stomata
thin inner and thick outer walls - allows to bend when turgid

Question 3

Epithelial tissue structure/function

Answer 3

Made up almost entirely of cells
Cells packed together closely by desmosomes or tight junctions
no blood vessels - receive nutrients by diffusion
Some smooth or some have projections (villi)
specialised - excretion, secretion,protection,absorption

Question 4

Neutrophils structure

Answer 4

Lysosomes conatining digestive enzymes to kill pathogen
Multilobed nucleus

Question 5

Erythrocytes structure

Answer 5

Biconcave shape - inc SA
No nucleus - more space for haemoglobin

Question 6

Sperm cell structure

Answer 6

lots of mitochondria to make ATP to move
acrosome containing enzymes to digest outer layer of egg
flagellum to swim

Question 7

Plant root cells adaptations

Answer 7

Thin cellulose cell wall - short diffusion pathway
Root hair cells (protrusions) - inc SA for osmosis
Vacuole contain cell sap - maintain conc gradient between cell and soil

Question 8

explain prokaryotic cells

Answer 8

single-celled organisms that lack membrane bound organelles
DNA stored in plasmids in cytoplasm

Question 9

function of bacterial capsule

Answer 9

protects cell from host immune system and stops excessive water loss