Introduction to Genetics, and Cells

• complete set of genetic instructions characteristic of an organism.

  genome
• What are chromosomes?

  Chromosomes are structures that are a product of DNA coiling in association with proteins.
• What are alleles?

  Alleles are different variants of a gene that encode for the production of different proteins.
• How are alleles related to mutations?

  Alleles are products of mutations.
• What is a mutation?

  A mutation is any heritable change in the DNA sequence and is the source of all genetic variation.
• What is a phenotype?

  A phenotype is the observable traits or features of an organism that are expressed by alleles.
• What is a genotype?

  A genotype is the set of alleles for a given trait carried by an organism.
• What is mitosis?

  Mitosis is a type of cell division in which one somatic cell gives rise to two new cells.
• What is meiosis?

  Meiosis is cell division involved in the production of gametes.
• What are the main branches of genetics?

  • Classical genetics (forward genetics)
  • Population genetics
  • Cytogenetics
  • Molecular genetics
• What does classical genetics study?

  Classical genetics studies the laws of hereditary transmission in living organisms.
• What is population genetics?

  Population genetics is the study of genes in populations of animals, plants, and microbes.
• What does cytogenetics study?

  Cytogenetics studies the structure of DNA within the cell nucleus, including the number and morphology of chromosomes.
• What is molecular genetics?

  Molecular genetics is the study of the molecular structure of DNA and its influence on the overall makeup of an organism.
• Who proposed the theory of epigenesis?

  William Harvey proposed the theory of epigenesis.
• What does the theory of epigenesis state?

  The theory of epigenesis states that an organism is derived from substances present in the egg that differentiate into adult structures during embryonic development.
• What is preformationism?

  Preformationism states that the fertilized egg contains a complete miniature adult called a homunculus.
• What is cell theory?

  Cell theory states that all organisms are composed of basic units called cells and that cells are derived from similar preexisting structures.
• Who disproved spontaneous generation?

  Louis Pasteur disproved spontaneous generation.
• When was Charles Darwin born?

  Charles Darwin was born in 1809.
• What was Charles Darwin's role on the HMS Beagle?

  Charles Darwin served as the ship's naturalist on the HMS Beagle.
• What did Darwin propose about existing species?

  Darwin proposed that existing species arose by descent with modification from ancestral species.
• What is the theory of natural selection?

  The theory of natural selection states that individuals with heritable traits that allow them to adapt to their environment are better able to survive and reproduce.
• What did Darwin publish in 1859?

  Darwin published "On the Origin of Species" in 1859.
• Who is known as the Father of Genetics?

  Gregor Mendel is known as the Father of Genetics.
• What did Mendel's paper describe?

  Mendel's paper described how traits are passed from one generation to the other using pea plants as models.
• What did Mendel conclude about traits in pea plants?

  Mendel concluded that each trait in pea plants is controlled by a pair of factors, now called genes.
• What is the diploid number (2n)?

  The diploid number (2n) is the characteristic number of chromosomes a eukaryote has in most of its cells.
• What are homologous chromosomes?

  Homologous chromosomes are pairs of chromosomes that are usually identical in size and have the same location of their centromeres.
• What is a karyotype?

  A karyotype is a profile of an individual's chromosomes, including their number and appearance.
• How do chromosomes behave during mitosis?

  During mitosis, chromosomes are copied and distributed to each daughter cell, resulting in both cells obtaining a diploid set of chromosomes.
• How do chromosomes behave during meiosis?

  During meiosis, cells receive only one chromosome from each chromosome pair, resulting in a haploid number (n) of chromosomes.
• What does the chromosomal theory of inheritance state?

  The chromosomal theory of inheritance states that inherited traits are controlled by genes residing on chromosomes, which are transmitted through gametes.
• What are the major chemical components of chromosomes?

  The major chemical components of chromosomes are DNA and proteins.
• Who were awarded the Nobel Prize in 1962 for their contribution to the structure of DNA?

  Maurice Wilkins, Francis Crick, and James Watson were awarded the Nobel Prize in 1962 for their contribution to the structure of DNA.
• What is the structure of DNA?

  DNA is a long, ladder-like macromolecule that twists to form a double helix made up of nucleotides.
• What are the four types of nucleotides found in DNA?

  The four types of nucleotides found in DNA are A (adenine), G (guanine), C (cytosine), and T (thymine).
• What are the base pairing rules in DNA?

  The base pairing rules in DNA are A=T and G=C.
• How does RNA differ from DNA?

  RNA is a single-stranded molecule that contains uracil (U) in place of thymine and has a different sugar than DNA.
• What is gene expression?

  Gene expression is the process by which the genetic information in DNA is expressed to form a functional gene product, usually a protein.