Life Science: Genetics and Heredity

Curly hair is determined by the genes passed from parents to offspring. Therefore, it is considered an inherited trait.

Hair length is a result of grooming and personal choice, not genetic code. It is an acquired characteristic, not an inherited trait.

Eye color is a classic example of a polygenic trait determined by the DNA inherited from biological parents.

While genetics play a role in body composition, weight is also significantly influenced by environmental factors such as diet, exercise, and lifestyle choices.

Height is a complex trait heavily influenced by the genes inherited from parents, making it an inherited trait.

In the structure of DNA, the nitrogenous base cytosine (C) always forms a hydrogen bond with guanine (G) according to Chargaff's rules.

Homozygous refers to an organism that has two identical alleles for a particular gene, such as AA or aa.

Heterozygous refers to an organism that has two different alleles for a particular gene, such as Aa.

Purebred is a term often used in breeding to describe an organism that is homozygous for a specific trait, meaning it will consistently pass that trait to its offspring.

A hybrid is the offspring of two different varieties or species, and in genetics, it refers to an organism that is heterozygous for the trait being studied.

A mutation is a permanent alteration in the DNA sequence that makes up a gene, such that the sequence differs from what is found in most people.

The double helix is the term used to describe the physical structure of the DNA molecule, which consists of two strands that wind around each other.

DNA replication is the biological process of producing two identical replicas of DNA from one original DNA molecule.

Genetics is the branch of biology concerned with the study of genes, genetic variation, and heredity in organisms.

The genotype is the set of genes in our DNA which is responsible for a particular trait, whereas the phenotype is the physical expression of those genes.

A recessive allele is one that is masked by a dominant allele, often described as the weaker allele in basic genetic models. Phenotype and genotype refer to the physical expression and genetic makeup, respectively, rather than the strength of an allele.

A dominant allele is one that expresses its trait even when only one copy is present, making it the stronger allele in simple Mendelian inheritance. Recessive alleles are masked, while genotype and phenotype are broader genetic terms.

Genes are the functional units of heredity that code for specific proteins, which result in observable traits. Alleles are variants of genes, while chromosomes and the double helix are structures containing DNA.

A gene is a specific segment of DNA located on a chromosome that carries instructions for a trait. Chromosomes are the larger structures, and the double helix is the shape of the DNA molecule itself.

The double helix is the term used to describe the twisted ladder or spiral staircase structure of the DNA molecule. The other options refer to genetic components or structures, not the shape of the molecule.

Chromosomes are threadlike structures made of DNA and proteins that are found in the nucleus of cells. DNA is coiled tightly around proteins to form these structures.

An allele is defined as one of two or more alternative forms of a gene that arise by mutation and are found at the same place on a chromosome. DNA is the molecule, and chromosomes are the structures containing genes.

Gregor Mendel is known as the father of genetics for his pioneering experiments with pea plants, which established the basic laws of inheritance. Watson, Crick, and Franklin are famous for their work on the structure of DNA.

Rosalind Franklin used X-ray crystallography to capture images of DNA, which were crucial for Watson and Crick to determine the double helix structure. She is widely recognized for this contribution.