Answer:
4. p.complement system c.saliva b.sneezing
Answer:
The correct answer would be 10.
The cell cycle can be divided into four phases namely gap 1 (G₁) phase , synthesis (S) phase, gap 2 (G₂) phase, and mitosis (M) phase.
DNA (deoxyribonuceic acid) content is only replicated and doubled in the S phase. However, the chromosome number remains the same. It can be explained as the number of chromosomes remains the same (2n) but number of chromatids doubles (4n) after S phase.
The number of chromatids restores to 2n in daughter cells after completion of mitosis.
Hence, if number of chromatids in metaphase was 20 i.e. 4n then the number of chromosomes (2n) would be 10.
Hence, 10 chromosomes or 5 pairs of chromosome would be present in the cell during its G₁ phase.
Prokaryotic bacteria are surrounded by a cell membrane that contains the transport proteins to regulate the entry and exit of materials through the cell, the cell wall to help maintain cell shape and structure, and the capsule, which aids against drying out and protects bacteria from a host's immune system.
<h3><u>Explanation:</u></h3>
Bacteria are the prokaryotic organisms that are found in every part of Earth. These organisms do have an interesting ultrastructure. The coverings of the bacteria are three in layer. They are
A. The outer capsule.
B. The middle cell wall.
C. The inner cell membrane.
The capsule is the outermost covering of bacteria that is formed of different slimy materials. These materials contains hygroscopic substances which can absorb water from the surroundings even when the water concentration in outside is very very low. This layer of protection outside bacteria help them to protect themselves against drying out at dry conditions.
The middle cell wall is formed of polymers of N acetyl glucosamine and N acetyl muramic acid. This layer is chitin in nature and is strong enough to maintain the shape and size of bacteria irrespective of outer conditions.
The innermost layer of bacteria is cell membrane which is formed of proteins and lipids bilayer and this cell membrane contains different transport for proteins which help in transport of different substances like water and nutrients inside the cell by means of active transport or passive diffusion.
Answer:
The correct answer is 4: "The exception to Mendelian laws of inheritance that best explains the mentioned symptoms is codominance".
Explanation:
In codominance, both alleles can be expressed. In these cases, heterozygote individuals<em> instead</em> of showing an <em>intermediate phenotype</em>, express both of the alleles. Their phenotype is an additive expression of their parents' genes.
In cystic fibrosis, there is a gene responsible for coding for a protein named "cystic fibrosis transmembrane conductance regulator, CFTR".
-Most of the people have two copies of the normal allele and produce the functional CFTR protein form.
-Patients with cystic fibrosis have two copies of the mutated allele and so produce the mutated and dysfunctional form for this protein.
-Heterozygote people possess only one normal CFTR allele and a mutated form for the same allele and produce a normal protein and a mutated protein.
In the last case, both alleles are codominant and they express in heterozygote individuals. Given the fact that the normal allele produces enough functional CFTR protein, these individuals do not have any adverse effect and the mutated allele is recessive at a physiological level.
This isn't possible except you have a system where there isn't competition and the survival of the fittest in the aspect of the food chain
