14: Operons allow prokaryotes to replicate DNA at the appropriate time.
Operons are specific regions of genes that are linked to a singular process. They ensure that the expression of these genes does not go unchecked and only occurs when necessary. Two key examples of this in humans are the lac operon and trp operon.
15. The central dogma of molecular biology is:
DNA to RNA to Proteins
Protein Synthesis occurs in 3 steps.
First our DNA is translated into RNA. Next the RNA is sequenced into Amino Acids by reading the corresponding 3-Base Codons. These Amino Acid sequences form various protein structures.
Answer:
A single gene on the Y chromosome plays a crucial role in the parental development of the testes.
Explanation:
Y chromosome is present only in males and this chromosomes is the distinguishing factor which separates males from females. It is the smallest chromosome but of utmost importance due to its sex determining feature. Up till now, studies show that Y chromosomes only carry limited amount of genes.
The Y chromosome, most importantly, comprises of the SRY gene. This is the gene responsible for determining the testis and for the development of the testis. The SRY gene is responsible for sex determination.
Answer:
B. There is less biodiversity in the high tide zone because the tidal changes make survival difficult.
Explanation:
The high tide and low tide zones are located on the seashore as the ocean water merges with land.
High tide zones are usually covered with water during high ocean tide while low tide zones are always submerged in water.
There is low biodiversity in the high tide zone because the tide here changes rapidly and organisms find it difficult to adapt. Organisms that inhabit here must be welll adapted to withstand peroids of high tides.
Answer:
Minerals can form in all geological environments, which allows them to have a wide range of chemical and physical conditions. Two forms of this are temperature and pressure. There are 4 main categories of mineral formations. Igneous is where the minerals crystalize from a melt. Sedimentary is where the raw materials of the mineral are particles from other rocks that have suffered from erosion and weathering. Metamorphic is where new minerals are created from earlier ones owing to the effects of change. Most of the time it's from increasing temperature and/or pressure. Hydrothermal is where the minerals are chemically precipitated from hot solutions in the earth.