Edexcel GCSE Biology (9-1) All-in-One Review

Comprehensive vocabulary flashcards covering the Edexcel GCSE Biology curriculum, including cell biology, genetics, human physiology, and medicine.

Nucleus

The compartment in a cell that controls the activities of the cell.

Cytoplasm

A jelly-like substance surrounding the nucleus where all chemical reactions take place.

Cell membrane

A single border surrounding a cell that controls the entry and exit of substances.

Mitochondria

The powerhouse of the cell that creates energy via aerobic respiration.

Aerobic Respiration

A process of creating energy that requires oxygen.

Fibrous ohms

Tiny dots inside the cell responsible for protein synthesis.

Cell wall

A structure surrounding a plant cell that supports the cell.

Vacuole

A rectangular structure in the middle of a plant cell that contains cell sap.

Chloroplasts

Green structures in plant cells containing chlorophyll where photosynthesis takes place.

Flagella

A little tail that helps bacteria move.

Luke Lloyd

The structure in a bacterial cell where genetic information is found instead of a distinct nucleus.

Plasmids

Tiny structures in bacteria containing genetic information, important for genetic engineering.

Acrosome

A special structure in the head of a sperm cell containing enzymes that break down the outer casing of the egg.

Haploid nucleus

A nucleus containing only one set of chromosomes ($23$ in humans).

Cilia

Small hair-type structures that waft back and forwards to move substances like eggs in the oviduct or pathogens in the trachea.

Organelles

Small structures found inside cells, such as mitochondria or a nucleus.

Tissue

A group of cells working together to perform the same function.

Organ system

A group of organs working together to perform the same function.

Resolving power

The ability of a microscope to distinguish between two separate points.

Magnification Formula

$$\text{Magnification} = \frac{\text{Image size}}{\text{Object size}}$$

Enzyme

A biological catalyst that speeds up the rate of a chemical reaction without being used up.

Active site

The biologically active part of an enzyme molecule where the substrate molecule binds.

Amylase

An enzyme made in the saliva glands, small intestine, and pancreas that breaks down starch into glucose.

Protease

An enzyme found in the stomach, small intestine, and pancreas that breaks down proteins into amino acids.

Lipase

An enzyme that breaks down lipids (fats) into fatty acids and glycerol.

Denatured

A state where an enzyme's active site has changed shape, meaning the substrate can no longer fit.

Benedict's reagent

A chemical used to test for glucose; it turns brick red when heated in a water bath if glucose is present.

Biuret reagent

A chemical reagent used to test for proteins, which turns purple in their presence.

Emulsion test

A test for fats involving ethanol and water that produces a milky white emulsion if fat is present.

Diffusion

The passive net movement of particles from an area of high concentration to an area of low concentration.

Osmosis

The net movement of water from an area of high water potential to an area of low water potential across a partially permeable membrane.

Active transport

The net movement of particles from an area of low concentration to an area of high concentration, which requires energy.

Mitosis

A type of cell division used for growth and repair that produces two genetically identical daughter cells.

Prophase

The stage of mitosis where the nucleus breaks down and spindle fibers form.

Metaphase

The stage of mitosis where chromosomes line up at the equator (middle) of the cell.

Stem cell

A cell that is not specialized and is capable of becoming any other type of cell.

Meristems

Groups of cells in plant shoots and root tips that allow the plant to grow continually throughout its life.

Cerebral cortex

The main part of the brain divided into two hemispheres; responsible for emotions, memory, and behavior.

Cerebellum

The part of the brain responsible for balance and maintaining posture.

Medulla oblongata

The control center of the brain that regulates breathing rate, heart rate, and reflexes.

CT scan

A scan that uses x-rays and a computer to build an image of the structures found within the brain.

PET scan

A scan that shows brain activity by detecting gamma rays produced by injected radioactive glucose.

Myelin sheath

A fatty substance surrounding the axon that insulates it and increases the speed of electrical impulse transmission.

Synapse

The gap between two neurons where electrical impulses are converted into chemical neurotransmitters.

Cornea

The part of the eye that refracts (bends) light as it enters.

Retina

The part of the eye containing photoreceptor cells (rods and cones) that are sensitive to light.

Accommodation

The process of the lens focusing light from different distances onto the retina.

Meiosis

A type of cell division used to produce four genetically varied gametes (sperm and egg cells).

Genome

The entire DNA belonging to an organism.

Alleles

Different forms of the same gene.

Genotype

The specific alleles an organism possesses (represented by letters).

Phenotype

The physical appearance of a particular trait.

Codominance

When both alleles in the genotype are expressed in the individual's phenotype.

Natural selection

The theory that individuals with favorable genetic variations are more likely to survive and reproduce.

Pentadactyl limb

A five-fingered limb structure common to many animals, suggesting evolution from a common ancestor.

Restriction enzyme

Biological scissors used to cut DNA at specific points during genetic engineering.

Vector (Biology)

An organism or structure (like a plasmid) used to transport biological material from one place to another.

Pathogen

A microorganism that causes disease.

Vibrio chloride

The waterborne bacteria responsible for causing cholera.

art Mesa Ninh

A chemical used to kill the Plasmodium parasite that causes malaria.

Lytic cycle

The process by which a virus hijacks a host cell to replicate itself until the cell bursts.

Phagocyte

A type of white blood cell that engulfs and ingests pathogens.

Lymphocyte

A white blood cell that recognizes antigens and secretes specific antibodies to destroy pathogens.

Herd immunity

When a large number of people are vaccinated against a disease, preventing its spread to unvaccinated individuals.

Aseptic techniques

Procedures used in laboratories to prevent contamination by microorganisms.

BMI Formula

$$\text{BMI} = \frac{\text{Mass (kg)}}{\text{Height (m)}^2}$$

Hybridoma

A new cell type formed by combining mouse cells, human cells, and cancer cells to produce antibodies.

Monoclonal antibody

A protein designed to target specific cells, such as cancer cells or pregnancy hormones.