Cell Biology Flashcards

Vocabulary flashcards covering the AQA 4.1 Cell Biology specification, including cell structure, division, and transport.

Eukaryotic cells

Cells that have a cell membrane, cytoplasm, and genetic material enclosed in a nucleus, such as plant and animal cells.

Prokaryotic cells

Bacterial cells that are much smaller than eukaryotes, having cytoplasm and a cell membrane surrounded by a cell wall, with genetic material as a single DNA loop not enclosed in a nucleus.

Plasmids

Small rings of DNA that may be found in bacterial (prokaryotic) cells.

Nucleus

The sub-cellular structure that contains genes and controls the activities of the cell.

Mitochondria

Sub-cellular structures where aerobic respiration takes place, providing energy for the cell.

Ribosomes

Sub-cellular structures responsible for protein synthesis.

Chloroplasts

Organelles found in plant cells that contain chlorophyll for photosynthesis.

Cell wall

A structure made of cellulose in plant and algal cells that strengthens the cell.

Cell specialisation

The process by which cells develop specific structures to perform particular functions, such as sperm cells, nerve cells, and muscle cells in animals.

Cell differentiation

The process occurring as an organism develops where cells change to form different types of specialised cells.

Resolution

The ability of a microscope to distinguish between two points; electron microscopes have a much higher resolving power than light microscopes.

Magnification Formula

$\text{magnification} = \frac{\text{size of image}}{\text{size of real object}}$.

Binary fission

The process of simple cell division by which bacteria multiply, which can occur as often as once every $20\,min$ given enough nutrients and suitable temperature.

Aseptic technique

Methods used to prepare uncontaminated cultures of microorganisms, such as sterilising Petri dishes and passing inoculating loops through a flame.

Chromosomes

DNA molecules found in the nucleus that carry a large number of genes, normally found in pairs in body cells.

Mitosis

The part of the cell cycle where a cell divides into two identical cells, essential for growth and development of multicellular organisms.

Stem cell

An undifferentiated cell of an organism capable of giving rise to many more cells of the same type and from which certain other cells can arise via differentiation.

Meristem tissue

Plant tissue found in the growing tips of roots and shoots that can differentiate into any type of plant cell throughout the life of the plant.

Therapeutic cloning

A process where an embryo is produced with the same genes as the patient, so stem cells harvested from it are not rejected by the patient's body.

Diffusion

The net movement 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 dilute solution to a more concentrated solution against a concentration gradient, which requires energy from respiration.