Science - Genetics

Key terms

Genetics:

the study of inheritance

DNA(deoxyribonucleic acid):

genetic make-up that carries the instructions for life

Double helix:

structure of DNA

Nucleotide:

a subunit of DNA

Deoxyribose:

a five-carbon sugar molecule found in DNA

Nitrogenous base:

one of adenine, guanine, cytosine, or thymine

Hydrogen bonds:

chemical bonds that hold the two strands of DNA together

Complementary pairing:

Adenine pair with Thymine;
Cytosine pair with Guanine (in DNA)

Chromosome:

a structure within a cell that contains an organism's genetic information, encoded in DNA

Gene:

a length of chromosome

RNA:

Ribonucleic acid, a nucleic acid present in all living cells. Its principal role is to act as a messenger carrying instructions from DNA for controlling the synthesis of proteins

Single helix:

structure of RNA

Ribose:

a five-carbon sugar molecule found in RNA

Transcription:

the process of making an RNA copy (mRNA) of a gene's DNA sequence carrying the gene's protein information encoded in DNA

Homologous chromosomes:

matching chromosomes

Non-homologous chromosomes:

non- matching chromosomes

Autosomes: in humas

chromosome pairs 1 to 22

Sex chromosomes:

in human, the 23rd pair of chromosomes that determines the sex of a personare either X or Y chromosomes.

Chromatid:

One of two molecules of DNA that makes up a chromosome

In RNA Thymine is swapped for

Uracil, which pairs with adenine.

Allele:

different forms of the same gene

Genotype:

the combination of alleles for a gene inherited from our parents

Homozygous:

having two identical alleles

Heterozygous:

having two different alleles

Punnett square:

a specialized grid to show crosses which helps determine the possible genes of an offspring