Answer:
d. Genes that play a role in the same metabolic pathway are organized into an operon.
Explanation:
In prokaryotic organisms like bacteria, polycistronic mRNAs exist which means that each gene does not have a separate promoter of its own. In fact many genes are under the control of a single promoter. These genes being a part of same metabolic pathway are organized into an operon. For example, lac operon and tryptophan operon. In lac operon, three genes named as β-galactosidase, permease and transacetylase are expressed under a single promoter which is known as lac promoter.
In contrast to this, in eukaryotes the mRNAs are monocistronic i.e. only a single gene is controlled under a single promoter.
Answer: l and ll only
Explanation: i took the test
Answer:
a. parasitism:
The parasite benefits by harming the host e.g hookworms and humans
b. commensalism
In this association, one species benefits while the other is unaffected (its not harm and dies not benefit) e.g. epiphytic orchids and trees
c. mutualism
Here, both species benefit as seen in rumen bacteria and cows
Explanation:
Parasitism = +/- relationship
The predator benefits by harming the host. E.g. hookworms and humans. The hookworm (parasite) eat man blood while man (host) loses blood to it.
Commensalism = +/0 relationship
One specie(s) benefits while the other specie(s) neither benefits nor is harmed. E.g. epiphytic orchids live on tree branches or tree trunks as it's habitat or shelter while the trees neither benefits nor is harmed
Mutualism = +/+ relationship
Both organisms benefit in this relationship. E.g. rumen microbes aids grass digestion in cows, while the microbes benefit as it obtain steady food or nutrient from the cow
Answer:
Joint - a joint is where two bones articulate
In this case, the femur and tibia form a joint.