Biology: Genetics And Punnett Squares Quiz!

Organisms that have two different alleles for a particular trait are said to be heterozygous. Heterozygous individuals have two different versions of a gene, or alleles, for a specific trait. This means that they inherited one allele from each parent. In contrast, homozygous individuals have two identical alleles for a trait, while hybrids are the offspring of two different species or varieties. Dominant refers to an allele that is expressed over another allele in heterozygous individuals.

When a heterozygous tall plant (Tt) is crossed with a short plant (tt), the offspring plants will have a 50% probability of being tall. This is because the heterozygous tall plant has one dominant allele (T) for tallness and one recessive allele (t) for shortness. When crossed with a short plant that has two recessive alleles (tt), there is a 50% chance that the offspring will inherit the dominant allele from the heterozygous parent and be tall.

The correct answer is Adenine, guanine, cytosine, and thymine. These four bases are the building blocks of DNA. They are nitrogenous bases that pair up with each other to form the double helix structure of DNA. Adenine pairs with thymine, and guanine pairs with cytosine. These base pairs are essential for DNA replication and genetic information storage and transmission.

Allele is the correct answer because it refers to the different versions or forms of a gene that exist within a population. Each allele can produce a different trait or characteristic, and individuals inherit two alleles for each gene, one from each parent. These alleles can be the same (homozygous) or different (heterozygous), and they contribute to the genetic diversity and variation observed in a population.

The probability of a hamster having black, fine hair is 4/16 or 1/4. This means that out of the total possible outcomes, 4 of them have black, fine hair.

In a dihybrid cross, two different traits are considered simultaneously. In this case, the proportion of peas that are green and smooth can be determined by multiplying the individual probabilities of each trait. Since each trait is controlled by a separate gene, they segregate independently. The probability of a pea being green is 3/4, and the probability of it being smooth is also 3/4. Therefore, the proportion of peas that are green and smooth is (3/4) * (3/4) = 9/16.

In this question, the cross is between a guinea pig with two dominant black fur alleles (BB) and a guinea pig with one dominant black fur allele and one recessive white fur allele (Bb). The dominant black fur allele (B) will always be expressed over the recessive white fur allele (b). Therefore, all of the offspring will have black fur. Since half of the offspring will inherit the dominant black fur allele (B) from the BB parent and the other half will inherit the dominant black fur allele (B) from the Bb parent, the probability of a hybrid offspring in this cross is 50%.

When the allele for hot flavor (H) is dominant over the allele for mild flavor (h), crossing a homozygous dominant plant (HH) with a recessive (mild) plant (hh) will result in all offspring having hot flavor. This is because the dominant allele (H) will always be expressed in the presence of the recessive allele (h). Therefore, the percentage of offspring with hot flavor is 100%.

A nucleotide is the basic unit of heredity. It is a building block of DNA and RNA, which carry genetic information. Nucleotides consist of a sugar molecule, a phosphate group, and a nitrogenous base. They form the backbone of DNA and RNA strands and encode the genetic instructions necessary for the development and functioning of living organisms. Proteins, chromosomes, and genes are all important components of heredity, but the nucleotide is the fundamental unit that carries and transmits genetic information.

When two heterozygous individuals (Aa) are crossed, the possible genotypes of the offspring are AA, Aa, and aa. The dominant phenotype is expressed in individuals with either the AA or Aa genotype. Therefore, the probability of an offspring having the dominant phenotype is 3 out of 4, or 75%.