Answer:
A.
Explanation:
Phototropism is most often observed in plants, but can also occur in other organisms such as fungi. The cells on the plant that are farthest from the light have a chemical called auxin that reacts when phototropism occurs.
Answer:
Instantaneous speed is found by taking the absolute value of instantaneous velocity, and it is always positive. Average speed is the total distance traveled divided by elapsed time.
Answer: D) Polygenic
Explanation: Polygenic inheritance describes the inheritance of traits that are determined by more than one gene. These genes, called polygenes, produce specific traits when they are expressed together. Polygenic traits have many possible phenotypes (physical characteristics) that are determined by interactions among several alleles. Examples of polygenic inheritance in humans include traits such as skin color, eye color, hair color, body shape, height, and weight.
Answer:
Isoniazid (INH) and rifampicin (RMP).
This is called MDR TB.
MDR TB is a particular type of drug resistant TB. It means that the TB bacteria that a person is infected with are resistant to two of the most important TB drugs, isoniazid (INH) and rifampicin (RMP). If bacteria are resistant to certain TB drugs this means that the drugs don’t work.
Answer:
Explanation:
Meiosis is a form of cell division that occurs in the sex cells of organisms. It ensures the reduction of a diploid cell to an haploid cell to allow for the formation of a diploid zygote after fertilization (contribution of both parents haploid sex cells to give a diploid zygote). Thus, this process is very essential and important.
The reduction is accomplished by 2 divisions after the duplication of chromosomes
- first division: separation of homologous pairs of chromosomes (this reduces the total in half)
- second division: separation of sister chromatids of a chromosome.
The rearrangement in meiosis occurs by crossing over/genetic recombination.
This is the exchange of genetic material between homologous pairs of chromosome bringing about a rearrangement and genetic variation
An example of a chromosomal abnormality that arises as a result of defects in this process is the Down Syndrome which is caused by a nondisjunction of the chromosomes 21 pair in a sex cell.
This condition produces offsprings that have some characteristic facial features, short stature etc
