Answer:
Each mutant would be mated to wild type and to every other mutant to create diploid strains. The diploids would be assayed for growth at permissive and restrictive temperature. Diploids formed by mating a mutant to a wild type that can grow at restrictive temperatures identify the mutation as recessive. Only recessive mutations can be studied using complementation analysis. Diploids formed by mating two recessive mutants identify mutations in the same gene if the diploid cannot grow at restrictive temperature (non-complementation), and they identify mutations in different genes if the diploids can grow at restrictive temperature (complementation).
Explanation:
Recessive mutations are those whose phenotypic effects are only visible in homo-zygous individuals. Moreover, a complementation test is a genetic technique used to determine if two different mutations associated with a phenotype colocalize in the same <em>locus</em> (i.e., they are alleles of the same gene) or affect two different <em>loci</em>. In diploid (2n) organisms, this test is performed by crossing two homo-zygous recessive mutants and then observing whether offspring have the wild-type phenotype. When two different recessive mutations localize in different <em>loci</em>, they can be considered as 'complementary' since the heterozygote condition may rescue the function lost in homo-zygous recessive mutants. In consequence, when two recessive mutations are combined in the same genetic background (i.e., in the same individual) and they produce the same phenotype, it is possible to determine that both mutations are alleles of the same gene/<em>locus</em>.
Answer:
The peripheral nervous system (PNS) is one of the two components of the nervous system, the other part is the central nervous system (CNS). The PNS consists of the nerves and ganglia outside the brain and spinal cord.[1] The main function of the PNS is to connect the CNS to the limbs and organs, essentially serving as a relay between the brain and spinal cord and the rest of the body.[2] Unlike the CNS, the PNS is not protected by the vertebral column and skull, or by the blood–brain barrier, which leaves it exposed to toxins and mechanical injuries. The peripheral nervous system is divided into the somatic nervous system and the autonomic nervous system. In the somatic nervous system, the cranial nerves are part of the PNS with the exception of the optic nerve(cranial nerve II), along with the retina. The second cranial nerve is not a true peripheral nerve but a tract of the diencephalon.[3]Cranial nerve ganglia originated in the CNS. However, the remaining ten cranial nerve axons extend beyond the brain and are therefore considered part of the PNS.[4] The autonomic nervous system is an involuntary control of smooth muscle and glands. The connection between CNS and organs allows the system to be in two different functional states: sympathetic and parasympathetic
Explanation:
Answer:
Natural selection
Explanation:
Sexual selection refers to the natural selection where the allele frequencies of a population are changed due to nonrandom mating between the individuals. Certain preferences for the mate by organisms result in sexual selection. It is mostly exhibited by females.
For example, peahen prefers the peacocks with elaborate tail features as their mate. The sexual selection also occurs when there is competition among the members of the same sex for a mate. This type of sexual selection is mostly exhibited by males and results in fighting and display.