Answer:
The internal membrane system is made up of different membranes and organelles present in the cytoplasm within eukaryotic cells. These membranes and organelles functions together to change, assemble, and convey proteins and lipids in the cell. They include the nuclear membrane, lysosomes, endoplasmic reticulum, Golgi apparatus, and vesicle. These structures also distinguish a eukaryotic cell from a prokaryotic cell as they cannot be found in prokaryotic cell.
Explanation:
The illustration depicts the deoxyribonucleic acid double helix.
DNA contains four nitrogenous bases: Adenine, cytosine, guanine, and thymine.
The base pairing are always as follows:
· adenine with thymine
· cytosine with guanine
Answer:
D) thymine
Answer:
<u>Behavioral isolation is demonstrated in species of finches. Their mating calls are distinct yet unique across species.</u>
Explanation:
Mutations arising from errors within gene replication often accumulate within populations, becoming more stable. They may lead to the formation of separate, genetically distinct populations called species. These new species arise via:
- allopatric speciation
- peripatric speciation
- parapatric speciation
- and sympatric speciation
Behavioral isolation is an isolating mechanism that is part of sympatric speciation. Here, there are apparent non-physical barriers to prevent mating, and several related species live within a population and gene-flow. However, reproductive isolation occurs through assortative mating (mate choice based on shared traits) which may lead to heteropatric speciation.
Commonly observed in birds, it involves distinct and unique courtship and mating signals. Mates only respond to those fitting the required behavioral patterns such as a courtship dance, nest building, foraging and songs.