Answer:During attachment and penetration, the virus attaches itself to a host cell and injects its genetic material into it. During uncoating, replication, and assembly, the viral DNA or RNA incorporates itself into the host cell's genetic material and induces it to replicate the viral genome.
Explanation:
The correct answer is
Stasis
Population becomes isolated
After rapid change in isolated population
Reintroduction
What is different concerning the DNA in bacterial cells as opposed to eukaryotic cells
o The amount of DNA present, whether the DNA is housed in a nucleus or not, and whether the DNA is linear or circular
• Which of these statements is true regarding cell division in the body of a growing teenaged human?
o Only a subset of cells is dividing at this point o We grow by cell division, but not all of our cells are dividing
• Dividing cells must copy their DNA
( replication ), segregate DNA and other cellular components during
( mitosis ) and split apart during
( cytokinesis)
• Our chromosomes exist as many sets of similar pairs with the EXCEPTION of our sex chromosomes o the sex chromosomes of the human female are also pairs. It is the X and Y of the male that break this rule •
Answer:
AaBb × aabb
Explanation:
A test cross is a cross between an unknown genotype (dominant phenotype) with a homozygous recessive genotype in order to discover the actual genotype of the species exhibiting dominant phenotype.
This is because one allele of a gene is capable of masking the expression of another, the allele masking is called DOMINANT allele while the allele being masked is called RECESSIVE allele. The combination of these two alleles is termed heterozygosity.
An organism that is phenotypically dominant for a specific trait may either be heterozygous or homozygous for that gene. For example, a plant gene for tallness with an dominant allele T, and recessive allele t. This plant will need tall if the genotype is TT (homozygous dominant) or Tt (heterozygous dominant). In order to know which of these genotypes the plant actually has, a test cross is conducted.
In this example, two genes A and B are involved. For the first gene, A represents dominant allele while a represents recessive allele. For the second gene, B represents dominant allele while b represents recessive allele.
In a cross involving parents AABB (homozygous dominant for both genes) and aabb (homozygous recessive for both genes), the F1 progeny will all exhibit phenotypic dominance (AaBb).
However, we cannot know the genotype by merely looking at the phenotype. We cannot ascertain yet whether the dominance is heterozygous or homozygous, hence the need for a test cross.
The test cross is between the dominant F1 progeny and a homozygous recessive i.e. AaBb × aabb. Some of the F2 generation will show recessive traits if the unknown genotype is heterozygous.
