Question | Answer |
Genetics | The study of traits (characteristics) and how they are inherited. |
Dominant allele | The one that the shows in a heterozygous genoype. |
Recessive allele | The one that is not expressed unless it’s genotype homozygous. |
Phenotype | The effect (that can be seen) of the genotype. |
Punnet Squares | Used to determine the phenotypes of the offspring using the genotypes of the parents. |
Incomplete Dominance | Form of inheritance where 2 alleles are expressed in the phenotype of a heterozygous genotype. |
Co-Dominance | The phenotype of the heterozygous organism is a combination of the phenotypes of the homozygous organisms. |
Genotype(s) of Blood Group 'O' | OO |
Genotype(s) of Blood Group 'A' | AA or AO |
Genotype(s) of Blood Group 'B' | BB or BO |
Genotype(s) of Blood Group 'AB' | AB |
DNA stands for _____________ | Deoxyribonucleic Acid |
What does DNA do? | It carries all of the gene information that determines the characteristics that you express. |
Who discovered DNA? | Watson & Crick, in 1953. |
What are the 4 bases in DNA? | Adenine, Thymine, Guanine, and Cytosine. |
What is a nucleotide? | A nucleotide is a building block consisting of: a sugar group,a phosphate group, and a nitrogen base. |
What is the complementary strand of TAGTTAC? | ATCAATG |
What is a mutation? | Any change in a gene or chromosome that may produce an alteration in the characteristic for which it codes. |
Will mutations be inherited? | No, unless they occur in the gametes or in the zygote cell. |
What is 'single-cell mutation'? | A type of mutation changes a single letter in the gene text. This results in the substitution of one amino acid for another in the protein. |
What disease is a result of a single-cell mutation? | Sickle-cell Anaemia. |
What are somatic cells? | Body cells. |
What are gametes? | Sex cells. |
What are mitosis & meiosis? | 2 types of cell division in animals. |
How many daughter cells does mitosis make? | It produces 2 daughter cells which are an exact copy of their parent cells (they have the same no. of chromosomes. |
What are the the daughter cells made from mitosis called? | They are called diploid cells, and have 46 chromosomes each (23 pairs). |
How many daughter cells does meiosis make? | Produces 4 daughter cells which are not exact copies of their parent cells. |
Why are the daughter cells made from meiosis not exact copies of their parents? | Because there are 2 divisions and each daughter cell contains half the number of chromosomes (23). |
What are the the daughter cells made from meiosis called? | They are called haploid cells, and have 23 chromosomes each. |
Where does mitosis occur? | In all body (somatic) cells (eg. skin cells, blood cells, muscle cells). |
Where does meiosis occur? | In sex cells (gametes). |
What is a genotype? | A combination of alleles. |
Where is DNA located? | Within the nucleus of all cells, thread-like structures known as chromosomes are found. On these chromosomes, there are bands called genes. This is where DNA is located. |
What is a genotype? | A combination of alleles. |
What 'states' can genotypes be in? | Homozygous or Heterozygous. |
What is a phenotype? | The effeect of the genotype (that can be seen). |
Where is DNA located? | Within the nucleus of all cells, thread-like structures known as chromosomes are found. On these chromosomes, there are bands called genes. This is where DNA is located. |
What is a 'condon'? | Letters of a gene (in sets of 3s), each of which signifies a different amino acid. |
How many possible condons are there? | Sixty-four. |
How many different amino acids are there? | Twenty. |
What 3 letters do all genes begin with? | ATG. |
What "stop" condons are there? | TAA, TAG, or TGA. |
What is a mutagen? | A mutation-causing agent. |
What are some mutagens? | X-rays, gamma rays, and ultraviolet light. |
Which cells are diploid? | Somatic cells (they have 2 sets of chromosomes; 2n). |
Which cells are haploid? | Gametes (they have 1 set of chromosomes; 1n). |
What is a zygote? | The initial cell formed when a new organism is produced by means of sexual reproduction. |
What is a Pedigree? | A “family tree” that is useful in getting background genetic information that can be used for medical reasons. |
Why can’t a non-tongue-roller be heterozygous for the condition? | A recessive allele will only be expressed in an individual if they have a homozygous genotype (tt). |
What are the types of inheritance? | Simple Inheritance, Incomplete Inheritance, Co-Dominanace, and Sex-Linked Inheritance. |
Blood types are what kind of inheritance? | Co-Dominance. |
How are the 4 bases of DNA paired together? | Adenine + Thymine (A+T) Guanine + Cytosine (G+C) |
How many bases does a segment of DNA have? | Up to 1000. |
Males of what kind of chromosome? | XY. |
Females have what kind of chromosome? | XX. |
How many pairs of non-sex chromosomes do humans have? | Twenty-two. |
What are Homologous Chromosomes? | Chromosome pairs of the same length, centromere position, and staining pattern, with genes for the same characteristics at the same locations (loci). |
What is the cell cycle? | The cell grows (G1 phase); Replicates its DNA (S phase); Prepares for cell division (G2 phase); Divides by mitosis (M phase). |
What happends during the M phase of the cell cycle? | Each chromosome is duplicated, and each replica remains attached to its original at the centromere portion of the chromosome. The two identical strands are called sister chromatids. |
What is a gene? | Someting that controls a particular characteristic. |