Answer:
The correct answer is the letter b. The endosymbiotic event that brought chloroplasts into Eukaryotic cells actually happened after Eukaryotic lineages diverged so many lineages never actually possessed chloroplasts
Explanation:
The plastid is an organelle linked to membarna found in the cells of eukaryotic organisms, which contains pigments used in photosynthesis. Some eukaryotic organisms over time have inherited the ability to photosynthesize from cyanobacteria by secondary endosymbiosis or ingestion, and are able to capture and sequester photosynthetic cells and chloroplasts, this process is known as kleptoplasty.
Answer:
Mendelian inheritance refers to the inheritance of traits controlled by a single gene with two alleles, one of which may be dominant to the other. Explanation:
Hope this helps
Answer: C). prolong the effect of epinephrine by maintaining elevated cAMP levels in the cytoplasm
Explanation: In the epinephrine pathway, binding of epinephrine to its receptor triggers a conformational change in the receptor and the interaction of the receptor with its associated Gs protein. This interaction causes the replacement of GDP bound to Gs protein with GTP thus activating the Gs protein. The activation of the Gs protein causes the alpha subunit of the Gs protein to dissociate and move to adenylyl cyclase, another membrane protein in the pathway. The association of the alpha subunit of the Gs protein with adenylyl cyclase activates adenylyl cyclase which in turn catalyzes the synthesis of cyclic AMP (cAMP) a second messenger. cAMP is quickly degraded to 5'-AMP by an enzyme phosphodiesterase. Inhibition of the activity of phosphodiesterase will increase the half life and the cytoplasmic level of cAMP thus potentiating the action of epinephrine.