Biology - Cell biology

Question 1

Eukaryote vs Prokaryote differences

Answer 1

Prokaryotes = single celled organisms, do not have nucleus, single loop of DNA found in cytoplasm, smaller plasmids also present
Cell wall made from peptidoglycan
Dont contain many sub-cellular structures as they are very small

Question 2

Eukaryote vs prokaryote size

Answer 2

10-100 micrometers vs less than 1 micrometer

Question 3

Millimetre to micrometer to nanometer

Answer 3

1mm =1000 um - 1x10 to the -6

1um = 1000nm - 1x10 to the -9

Question 4

How is a nerve cell specialised?

Answer 4

1. Has cell body where most cellular structures are and where protein synthesis takes place
2. Extensions of the cytoplasm form dendrites (receive signals) and axons (transmit signals), allows intra-neuron communication, muscles and gland cells
   3 Axon covered with fatty myelin sheath, acts as insulator to speed up nerve impulses

Question 5

How are muscle cells specialised?

Answer 5

1. Have layers of protein filaments which allow for sliding of layers which allows muscle contraction
2. Lots of mitochondria to provide energy via respiration
3. Skeletal muscle fuse during development to from multi nucleated cells that contract in unison

Question 6

How are sperm cells specialised?

Answer 6

1. Head contains nucleus with 23 chromosomes
   2, Acrosome at the head has digestive enzymes which break down the outer layer of the egg
2. Mid-piece packed with mitochondria to provide energy via respiration
3. Flagellum allows for swimming/movement