GCSE Biology Specification

GCSE Biology (8461) Specification Flashcards

Cells

The basic unit of all forms of life.

Eukaryotic cells

Plant and animal cells that have a cell membrane, cytoplasm, and genetic material enclosed in a nucleus.

Prokaryotic cells

Bacterial cells that are much smaller, have cytoplasm, a cell membrane, and a cell wall, but no nucleus.

Sub-cellular structures

Structures within cells, including the nucleus, cell membranes, mitochondria, and chloroplasts, that perform specific functions.

Cell differentiation

The process by which cells become specialized to carry out particular functions.

Stem cell

A cell that can differentiate into many different types of cells.

Diffusion

The spreading out of particles from an area of higher concentration to an area of lower concentration.

Osmosis

The diffusion of water from a dilute solution to a concentrated solution through a partially permeable membrane.

Active transport

The movement of substances from a more dilute solution to a more concentrated solution, requiring energy from respiration.

Tissue

A group of cells with a similar structure and function.

Organs

Aggregations of tissues performing specific functions.

Organ systems

Organs organized into systems that work together to form organisms.

Enzymes

Biological catalysts that speed up specific reactions in living organisms.

Pathogens

Microorganisms that cause infectious disease.

Human defense systems

The non-specific defense systems of the human body against pathogens, including the skin, nose, trachea, bronchi, and stomach.

Vaccination

Introducing small quantities of dead or inactive pathogens into the body to stimulate antibody production.

Antibiotics

Medicines that help cure bacterial disease by killing infective bacteria inside the body.

Homeostasis

The regulation of the internal conditions of a cell or organism to maintain optimum conditions for function.

Receptors

Cells that detect stimuli (changes in the environment).

Effectors

Muscles or glands that bring about responses which restore optimum levels.

Hormones

Chemicals secreted by glands directly into the bloodstream.

Type 1 diabetes

A disorder in which the pancreas fails to produce sufficient insulin.

Type 2 diabetes

A condition in which body cells no longer respond to insulin produced by the pancreas.

Sexual reproduction

The joining (fusion) of male and female gametes, leading to variety in the offspring.

Asexual reproduction

Reproduction involving only one parent and no fusion of gametes, leading to genetically identical offspring.

DNA

A chemical composed of two strands forming a double helix that carries genetic information.

Gene

A small section of DNA on a chromosome that codes for a particular sequence of amino acids to make a specific protein.

Genome

The entire genetic material of an organism.

Alleles

Different forms of a gene.

Genotype

The alleles present in an organism.

Phenotype

The characteristics that can be expressed as a result of the genotype.

Evolution

A change in the inherited characteristics of a population over time through natural selection.

Selective breeding

The process by which humans breed plants and animals for particular genetic characteristics.

Genetic engineering

Modifying the genome of an organism by introducing a gene from another organism to give a desired characteristic.

Biodiversity

The variety of all the different species of organisms on Earth or within an ecosystem.

Ecosystem

The interaction of a community of living organisms with the non-living parts of their environment.

Extremophiles

Organisms adapted to live in environments that are very extreme, such as high temperature, pressure, or salt concentration.

Food security

Having enough food to feed a population.