In the mid-1800s, an Austrian monk named Gregor Mendel Opens in modal popup window began his own experiments with plants. Unlike his predecessors, he used rigorous scientific methods in his experiments.
Mendel conducted his experiments with pea plants, which he grew in the garden of his monastery. The plants are easy to grow, reproduce quickly, and have several distinct characteristics Opens in modal popup window , or features, that are easy to observe. Characteristics of pea plants include flower color, seed color, and pea pod shape.
<span>Moreover, Mendel knew that each characteristic exists as one of two traits Opens in modal popup window , or forms of the character. For example, the seed color characteristic exists as one of two traits: green or yellow.</span>
MRNA is a short lived form of genetic information that is used in transcribing the genetic information, hence it is not very useful for analysis since it is fragile and wrong transcriptions happen quite often. SNPs (Single Nucleotide Polymorphisms) are a form of genetic mutation; they are more frequent than most other mutations since a single transription error may lead to this. While SNPs are important in genetic analysis and getting information about causes of disease, they are not very helpful in determining your maternal lineage. Similarly, while nuclear DNA contains a large portion of our genetic information, half of it is from our fathers and half from our mothers, so the analysis becomes hazy very soon. Mitochondrial DNA instead is directly passed down from mother to her offspring since the embryo contains only the mitochondria of the ovary. Thus, studying differences between mitochondrial DNA, one can gain information about his maternal lineage and go back to Mitochondrial Eve, the person from which all living persons have gotten their mitochondria from. Thus, the correct answer is c.
Answer:
Epstein-Barr virus
Explanation:
Epstein-Barr virus (EBV) is most widespread in the human population. It spreads through bodily fluids such as saliva. EBV is the virus which can cause or affect infectious mononucleosis also known as mono and other illnesses. After you get infected by EBV, the virus become inactive in our body. In some cases, virus may reactive, peoples who's having weak immune system are more likely to develop symptoms if virus is reactive.
Symptoms: Symptoms of EBV includes Fever, swollen liver, rash, enlarged spleen etc.
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.
