6.Prokarytes differ from eukaryotes by Select one:
O a. enclosing their DNA in a nucleus.
O b. by having mitochondria.
O c. by being multicellular.
O d. by having the DNA in the nucleoid area.

a. enclosing their DNA in a nucleus.

Explanation:

Prokaryotes in general have no membrane bound organelles. The cells are enclosed in a plasma membrane though .

explanation:

b,bacteria convert nitrates

into nitrogen gas.

d,plants and animals take in

and use nitrogen compounds.

e,bacteria break down waste    

products and return nitrogen  

to the soil.

a,bacteria convert atmospheric

nitrogen to ammonia.

c,bacteria convert ammonia

to nitrites and nitrates.

the menstrual cycle – higher tier. negative feedback mechanisms affect the production of hormones in the menstrual cycle. oestrogen also stimulates the release of lh (luteinising hormone) from the pituitary gland, which in turn controls the production of progesterone.