Key Vocab

Question 1

Adaptations

Answer 1

Traits/phenotypes which allow an organism to better survive in its environment.

Question 2

Allele

Answer 2

An alternative version of a gene. Alleles produce variation in individuals (e.g., B,b = Brown eyes, blue eyes)

Question 3

Amino acids

Answer 3

The building blocks of protein

Question 4

Ancestor

Answer 4

An organism (or species) from which other organisms (or species) have evolved.

Question 5

Antiparallel

Answer 5

The two strands of DNA molecule run in opposite directions.

Question 6

Bases

Answer 6

A (adenine), T (thymine), G (guanine), C (cytosine).

Question 7

Asexual reproduction

Answer 7

Requires only one parent. All offspring are genetically identical to the parent.

Question 8

Complementary Base Pairs

Answer 8

A:T (Apples in the Tree) and G:C (Cars in the Garage).
Ensures the genetic code is replicated correctly during DNA replication.

Question 9

Crossing-over

Answer 9

Swapping of DNA between homologous chromosomes during the meiosis process. Increases genetic variation.

Question 10

Chromosome

Answer 10

A long strand of DNA found in the nucleus of every cell. Contains a specific set of genetic information.

Question 11

DNA

Answer 11

Deoxyribonucleic Acid - A molecule that carries the genetic code.

Question 12

DNA sequencing

Answer 12

The process of finding out the exact order of bases on a length of DNA

Question 13

Dominant

Answer 13

An allele that is always expressed when it is present. Represented using capital letters (e.g., BB, Bb).

Question 14

Evolution

Answer 14

Gradual change in the genetic code of organisms over a long period of time. May result in formation of new species.

Question 15

Gametes

Answer 15

Sex cells containing half the chromosomes of the parent.

Question 16

Fertilisation

Answer 16

The process where the DNA from an egg and sperm fuse together.

Question 17

Genome

Answer 17

All the DNA in a single cell of an organism
.

Question 18

Gene

Answer 18

A short segment of DNA that codes for a particular protein/phenotype.

Question 19

Genetic Code

Answer 19

The bases of a gene are read in sets of three and each triplet codes for amino acid, which in turn, are joined to make a protein.

Question 20

Gene Marker

Answer 20

A short segment of DNA that can be used to follow inheritance of a trait (especially if it is not visible) or determine relatedness of different organisms.

Question 21

Genetic variation

Answer 21

The total number of different alleles in a population of organisms.

Question 22

Genotype

Answer 22

The combination of alleles for a gene (e.g., BB, Bb, bb).

Question 23

Genotypic ratio

Answer 23

The predicted ratio of inheritance of alleles from mating of two individuals.

Question 24

Heterozygous

Answer 24

Two different alleles in a genotype (e.g., Bb).

Question 25

Homozygous

Answer 25

Two alleles in a genotype are the same (e.g., BB or bb)

Question 26

Homologous pairs of chromosomes

Answer 26

Two chromosomes in a cell with the same genes on them. One chromosome is inherited from each parent.

Question 27

Independent segregation

Answer 27

Homologous chromosomes line up at random and independently of other homologous chromosomes during the process of meiosis.

Question 28

Karyotype

Answer 28

A picture of all the chromosomes in a cell, ordered from largest to smallest in homologous pairs.

Question 29

Meiosis

Answer 29

A type of cell division which produces egg and sperm cells (gametes) with half the number of chromosomes of the parent cell.

Question 30

Mutation

Answer 30

A permanent change in the DNA.

Question 31

Offspring

Answer 31

The resulting individuals of reproduction.

Question 32

Pedigree chart

Answer 32

A branching tree diagram that tracks alleles/traits being passed through a family.

Question 33

Phenotype

Answer 33

How a gene is expressed as a protein/phenotype trait.

Question 34

Phenotype ratio

Answer 34

The predicted ratio of phenotypes of offspring of a genetic cross.

Question 35

Phylogenetic Tree

Answer 35

A diagram that orders organisms in relationship to how closely related they are. Usually start with a common ancestor on the far left.

Question 36

Proteins

Answer 36

Polymers of amino acids that make up our traits.

Question 37

Punnett square

Answer 37

A method of showing the probability of all the potential offspring genotypes and phenotypes that can occur from mating two individuals.

Question 38

Population

Answer 38

Number of organisms of the same species living in a defined area.

Question 39

Recessive

Answer 39

An allele that is only expressed in the phenotype when the genotype is homozygous (bb).

Question 40

Sexual reproduction

Answer 40

Reproduction involving two parents. Offspring inherit half their DNA from each parent.

Question 41

Species

Answer 41

A group of organisms that can breed with each other and produce fertile offspring.

Question 42

Trait

Answer 42

A feature of an organism (phenotype).

Question 43

Triplet Code

Answer 43

Bases of genes are read in threes (triplets), each triplet codes for an amino acid to build a protein.

Question 44

Gene pool

Answer 44

All the alleles present in a population

Question 45

Linked genes

Answer 45

Where genes are on the same chromosome.

Question 46

Unlinked genes

Answer 46

Genes are on different chromosomes

Question 47

Locus

Answer 47

Position that a given gene occupies on a chromosome

Question 48

Chromatid

Answer 48

1 "arm" of a replicated chromosome

Question 49

Centromere

Answer 49

Where two homologous chromatids are joined

Question 50

Sister chromatids

Answer 50

The two chromatids on one chromosome

Question 51

Non sister chromatids

Answer 51

Two chromatids that are on different chromosomes in a homologous pair