A-Level/IGCSE Biology (0610) Lecture Notes Flashcards

Comprehensive vocabulary flashcards covering inheritance, cell division, genetic selection, ecology, and biotechnology based on the provided Biology 0610 notes.

Inheritance

The transmission of genetic information from one generation to the next.

Genetics

The study of inheritance.

Chromosome

A thread-like structure made up of DNA and proteins which carry genetic information in the form of genes.

Gene

A length of DNA coding for a particular protein.

DNA (deoxyribonucleic acid)

The genetic material that controls how a cell functions by deciding the shape and function of proteins like enzymes.

Protein synthesis

The process where a gene is copied onto mRNA, which then passes through ribosomes to assemble amino acids into proteins.

Diploid nucleus

A nucleus with a full set or two sets of chromosomes, which is $46$ in human somatic/body cells.

Haploid nucleus

A nucleus with one set of chromosomes, such as the $23$ chromosomes found in human gametes.

Mitosis

Nuclear division producing two genetically identical cells, maintaining the diploid number of chromosomes.

Meiosis

Cell division in which a cell divides to produce four daughter cells having half the number of chromosomes, resulting in genetic variation.

Stem Cells

Unspecialized cells which differentiate to form cells of specific structure and function like skin cells, brain cells, or blood cells.

Allele

An alternative form of a gene, occupying the same position (loci) on homologous chromosomes.

Dominant allele

An allele which expresses itself in the phenotype, suppressing the effects of the other allele of the pair.

Recessive allele

An allele which cannot express itself in the presence of a dominant allele and is expressed only in a homozygous state.

Genotype

The genetic makeup of an individual, consisting of all the alleles which control its characteristics.

Phenotype

The physical appearance or outward expression of a gene, such as height or eye color.

Homozygous

Having a pair of identical alleles of a gene.

Heterozygous

Having a pair of contrasting alleles of a given gene, as seen in hybrids.

Codominance

When alleles are expressed equally in the phenotype and intermediate features are produced.

Sex-linked characteristic

A characteristic where the responsible gene is located on a sex chromosome, often resulting in higher frequency in one sex.

Variation

The differences that exist between organisms of the same species and even different species.

Continuous variation

Variation where individuals show a range of phenotypes between two extremes, such as height or weight.

Discontinuous variation

Variation where individuals are grouped into limited, distinct phenotypes with no intermediates, such as blood groups.

Mutation

An unpredictable change in a gene or a chromosome.

Adaptive feature

A genetic feature of an organism that enables it to survive and reproduce in its environment.

Xerophytes

Plants adapted to surviving in very dry or desert conditions through features like thick waxy cuticles and sunken stomata.

Hydrophytes

Plants that survive in very wet places, characterized by thin cuticles and large air spaces for floating.

Natural Selection

The process by which organisms with advantageous adaptive features survive and pass on their genes to the next generation.

Selective Breeding (Artificial Selection)

When humans choose which animals to breed or plants to grow based on favorable or desirable features.

Population

A group of organisms of the same species living in the same habitat at the same time.

Ecosystem

A community of organisms interacting among themselves and their physical environment.

Niche

The role an organism plays in its ecosystem and the way it lives its life.

Trophic Level

The feeding position of an organism in a food chain.

Decomposers

Organisms like bacteria and fungi that feed on dead plants and animals and cause the decay of organic materials.

Eutrophication

The process where excessive fertilizers cause rapid growth of aquatic plants, leading to oxygen depletion as they decompose.

Biotechnology

The use of organisms to carry out processes that produce substances humans want.

Genetic Modification

The transfer of a gene from one species to another species.

Monoculture

The agricultural practice where a large piece of land is used to grow only one type of crop.

Sustainable resource

A resource that can be replaced or is readily available, allowing for use without running out.