Unit 3 List 2 DNA & Heredity JGC

Question 1

Allele

Answer 1

one of two or more alternative forms of a gene that arise by mutation and are found at the same place on a chromosome.

Question 2

Centromere

Answer 2

the region of a chromosome to which the microtubules of the spindle attach, via the kinetochore, during cell division.

Question 3

Chromatid

Answer 3

one of the two identical halves of a chromosome that has been replicated in preparation for cell division.

Question 4

Chromosome

Answer 4

a threadlike structure of nucleic acids and protein found in the nucleus of most living cells, carrying genetic information in the form of genes.

Question 5

Codon (chart)

Answer 5

The RNA codon chart helps us to identify which codons specify which amino acids. Codon recognition describes the ability of codons to match with the appropriate amino acids. Good codon recognition is essential to the correct assembly of polypeptides, which in turn leads to the production of the right proteins.

Question 6

Crossing Over

Answer 6

a cellular process that happens during meiosis when chromosomes of the same type are lined up.

Question 7

Daughter Cell

Answer 7

the cells that are formed after cell division.

Question 8

Deletion

Answer 8

A type of genetic change that involves the absence of a segment of DNA.

Question 9

Diploid

Answer 9

(of a cell or nucleus) containing two complete sets of chromosomes, one from each parent.

Question 10

DNA

Answer 10

Deoxyribonucleic acid (abbreviated DNA) is the molecule that carries genetic information for the development and functioning of an organism. DNA is made of two linked strands that wind around each other to resemble a twisted ladder — a shape known as a double helix.

Question 11

Fertilization

Answer 11

Fertilization is defined as the union of two gametes. During fertilization, sperm and egg fuse to form a diploid zygote to initiate prenatal development.

Question 12

Frameshift

Answer 12

A frameshift mutation is a genetic mutation caused by a deletion or insertion in a DNA sequence that shifts the way the sequence is read.

Question 13

Gamete

Answer 13

a mature haploid male or female germ cell which is able to unite with another of the opposite sex in sexual reproduction to form a zygote.

Question 14

Gene

Answer 14

(in informal use) a unit of heredity which is transferred from a parent to offspring and is held to determine some characteristic of the offspring.

Question 15

Gene Mutation

Answer 15

is a change in one or more genes. Some mutations can lead to genetic disorders or illnesses.

Question 16

Genetic Code

Answer 16

The genetic code is the set of rules used by living cells to translate information encoded within genetic material into proteins.

Question 17

Genetic Variation

Answer 17

Genetic variation is the difference in DNA among individuals or the differences between populations among the same species. The multiple sources of genetic variation include mutation and genetic recombination.

Question 18

Haploid

Answer 18

Haploid refers to the presence of a single set of chromosomes in an organism’s cells.

Question 19

Homologous Chromosome

Answer 19

A pair of homologous chromosomes, or homologs, is a set of one maternal and one paternal chromosome that pair up with each other inside a cell during fertilization.

Question 20

Independent Assortment

Answer 20

describes how different genes independently separate from one another when reproductive cells develop.

Question 21

Insertion

Answer 21

A type of genetic change that involves the addition of a segment of DNA.

Question 22

Meiosis

Answer 22

a type of cell division in sexually reproducing organisms that reduces the number of chromosomes in gametes

Question 23

Meiosis I

Answer 23

homologous chromosomes first pair with one another and then segregate to different daughter cells.

Question 24

Meiosis II

Answer 24

the second division in meiosis in which chromatids of each chromosome are segregated equally into daughter cells.

Question 25

Monosomy

Answer 25

Monosomy refers to the condition in which only one chromosome from a pair is present in cells rather than the two copies usually found in diploid cells.

Question 26

Mutagen

Answer 26

A mutagen is a chemical or physical agent capable of inducing changes in DNA called mutations.

Question 27

Mutation

Answer 27

Any change in the DNA sequence of a cell.

Question 28

Nondisjunction

Answer 28

Nondisjunction means that a pair of homologous chromosomes has failed to separate or segregate at anaphase so that both chromosomes of the pair pass to the same daughter cell.

Question 29

Offspring

Answer 29

a person’s child or children.

Question 30

Parent Cell

Answer 30

A cell that is the source of other cells

Question 31

Point Mutation

Answer 31

A point mutation occurs in a genome when a single base pair is added, deleted or changed.

Question 32

Replication

Answer 32

In molecular biology, DNA replication is the biological process of producing two identical replicas of DNA from one original DNA molecule. DNA replication occurs in all living organisms acting as the most essential part of biological inheritance.

Question 33

Sexual Reproduction

Answer 33

the production of new organisms by the combination of genetic information of two individuals of different sexes.

Question 34

Somatic Cells

Answer 34

any cell of a living organism other than the reproductive cells.

Question 35

Substitution

Answer 35

a type of mutation in which one nucleotide is replaced by a different nucleotide.

Question 36

Trisomy

Answer 36

A trisomy is a chromosomal condition characterised by an additional chromosome.

Question 37

Trait

Answer 37

a genetically determined characteristic.