There are many types of natural selection like direct selection, disruptive selection and stabilizing selection.
The situation given is that a population of mice lives in a city. The largest mice tend to be killed by predators and the smallest mice cannot compete for food.
The type of selection here is stabilizing selection. It is a type of natural selection in which there is decrease in genetic diversity as the population stabilizes.
Answer:
Histidine- Proline- Tryptophan- Stop codon
Explanation:
The mRNA strand in the question is produced as a result of a process called TRANSCRIPTION. However, the mRNA transcript is further used to synthesize an amino acid sequence in a process called TRANSLATION. The mRNA sequence is read in a group of three nucleotide bases called CODON.
Each codon specifies an amino acid which is represented in the GENETIC CODE. In this case, a sequence of mRNA strand is given as: CACCCAUGGUGA
The following codons in the sequence specify the following amino acid:
CAC - Histidine
CCA - Proline
UGG - Tryptophan
UGA - Stop codon
Hence, the amino acid sequence encoded by the given mRNA strand is Histidine- Proline- Tryptophan- Stop codon.
N.B: After a stop codon (UGA, UAA, UAG) is encountered, the translation process stops.
Answer:
A) a physiological desire to consume food is the correct answer.
Explanation:
- Hunger is a feeling that the person needs food to eat.
- Hunger makes the body weak and vulnerable to infections because the body does not get adequate food to fight against the infections and due to hunger people suffer from malnutrition and if children remain hungry they often have abnormal in their growth.
- hunger is caused because of poverty, job instability, food shortages, poor infrastructure, nutritional quality.
- Symptoms of hunger are:
- Feeling of growling and emptiness in the stomach.
- Dizziness
- Gurgling in stomach
- not able to concentration
- headache
- irritability
- nausea
The cell wall contains not only cellulose and protein, but other polysaccharides as well. The cell wall provides structural support and protection. Pores in the cell wall allow water and nutrients to move into and out of the cell. The cell wall also prevents the plant cell from bursting when water enters the cell.
Indeterminate cleavage results in identical cells capable of forming an embryo while determinate cells do not result in cells which are capable to develop embryo.
Indeterminate is superior to determinate cleavage.
Explanation:
Cleavage is the division of cells in the early embryonic stage. The two stages of cleavage described here are:
In indeterminate cleavage or regulative cleavage occurs when an embryo divides, each cell is capable of developing into complete embryo. eg: Deuterosomes
In determinate cleavage the resulting embryonic cells of blastomere cannot develop into embryos. It is also called as mosaic cleavage. The essential part of the cell might be missing which does not let the cell survive. eg: Protosomes
Indeterminate cleavage is of great importance as the cell grows and can produce new organism. The complete identical twin is formed. Its application can be seen in tomato plants.
3. All animals do not display intermediate cleavage because growth from intermediate cleavage is continuous and does not stop after adulthood which is not possible in animals.
