Science - Biology (Genetics)

Key Terms

Allele

Alternate form of a gene for a particular characteristic.

Amino Acid

An organic compound that forms the building blocks of proteins.

Amniocentesis

Type of prenatal screening where a sample is collected from the amniotic fluid surrounding the fetus.

Asexual Reproduction

Reproduction that does not involve the fusion of gametes (sex cells).

Autosome

Non-sex chromosome.

Carrier

An individual that carries, but does not show signs of, the recessive trait.

Cell

Building blocks of life.

Centromere

A section of chromosome that links sister chromatids.

Chargaff’s Rule

Adenine x Thymine _ Cytosine x Guanine

Chromatid

One identical half of a replicated chromosome.

Chromosome

Structure inside the nucleus that contains the DNA that carries genetic information.

Clones

Genetically identical copies.

Codon

Sequence of three nucleotides in DNA/RNA that acts as a code.

Cytogenetics

The study of heredity at a cellular level.

Deoxyribose

The sugar in the nucleotides that make up DNA.

Deoxyribonucleic Acid (DNA)

A substance that contains genetic information.

Diploid

The possession of two copies of each chromosome in a cell.

Break

Break

DNA Ligase

An enzyme that joins DNA fragments together.

DNA Replication

Process that results in DNA making a precise copy of itself.

Dominant

A trait (phenotype) that requires only one allele to be present.

Fertilisation

Penetration of the ovum by a sperm.

Gametes

Sex cells.

Gene

Segment of a DNA molecule that determines an organism’s characteristics.

Gene Therapy

Altering genes with the intention of treating or curing.

Genetically Modified Organism

An organism where the genome has been altered.

Genetics

Study of inheritance.

Genome

The complete set of genes present.

Genotype

Genetic instructions inherited from parent/s.

Haploid

The possession of one copy of each chromosome in a cell.

Heterozygous

A genotype where the two alleles are different.

Homozygous

A genotype where the two alleles are identical.

Homozygous Dominant

A genotype where both alleles for the dominant trait are present.

Homozygous Recessive

A genotype where both alleles for the recessive trait are present.

Inheritance

Genetic transmission of characteristics.

Maternal Chromosome

Chromosome from the ovum.

Meiosis

Cell division process - New cells with half of the chromosomes.

Messenger RNA (mRNA)

Single-stranded RNA that carries genetic information to a ribosome to be translated into a protein.

Mitosis

Cell division process - Genetically identical cells with the same number of offspring.

Monomers

Small molecules that build larger molecules (polymers).

Mutagen

Factor that can induce or increase the rate of mutations.

Mutation

Change to DNA sequence.

Nucleotide

Compounds containing a sugar part, a phosphate part and a nitrogen-containing base.

Nucleus