IGCSE Biology: Inheritance (Part 1)

Vocabulary flashcards covering key definitions and biological terms from Chapter 17 (Part 1) on Inheritance, including chromosomes, gene expression, protein synthesis, and cell division.

Inheritance

The process by which genetic information is passed from parents to offspring.

Chromosomes

Structures located in the nucleus of a cell, made of DNA which contains genetic information in the form of genes.

Gene

A length of DNA that codes for a protein.

Allele

An alternative form of a gene.

Sex chromosomes

The pair of chromosomes ($2$ out of the $46$ chromosomes in humans) that determines the sex or gender of an individual.

Punnett square

A genetic diagram where chromosomes or alleles are placed in boxes to demonstrate patterns of inheritance, such as sex inheritance.

Messenger RNA (mRNA)

A single-stranded copy of a gene that copies the DNA base sequences in the nucleus and carries them to the cytoplasm.

Transcription

The process in the nucleus where a gene coding for a protein is copied to produce an mRNA molecule.

Translation

The process where ribosomes pass along the mRNA strand and assemble amino acids into protein molecules in a specific order based on base sequences.

Gene expression

The process that occurs when a gene is switched on in a cell, leading to the production of its corresponding protein.

Haploid nucleus

A nucleus containing a single set of chromosomes, meaning it has one of each type of chromosome (such as the $23$ chromosomes in human gametes).

Diploid nucleus

A nucleus containing two sets of chromosomes, meaning it has a pair of each type of chromosome (such as $23$ pairs or $46$ chromosomes in human body cells).

Mitosis

Nuclear division giving rise to genetically identical cells.

Stem cells

Unspecialized cells that divide by mitosis to produce daughter cells that can become specialized for specific functions.

Zygote

A fertilized egg cell that acts as a stem cell, possessing the ability to divide by mitosis and specialize into different cell types during early development.

Meiosis

A type of nuclear division, also known as a reduction division, in which the chromosome number is halved from diploid to haploid, resulting in genetically different cells.