Biology Exam Revision: Cells, Organisms, and Ecosystems

These flashcards cover key vocabulary and concepts from biology pertaining to cells, living organisms, and ecosystem dynamics, tailored for exam revision.

Cell Theory

All cells are the smallest unit of life, all living things are composed of cells, and every cell comes from a pre-existing cell.

Prokaryotic Cells

Simpler cells without a nucleus or membrane-bound organelles, typically unicellular, such as bacteria.

Eukaryotic Cells

More complex cells with a nucleus and membrane-bound organelles that can be unicellular or multicellular.

Binary Fission

A method of asexual reproduction by which a single prokaryotic cell divides into two identical cells.

Chloroplasts

Organelles in plants responsible for photosynthesis, converting light energy into chemical energy.

Photosynthesis Equation

CO2 + H2O → O2 + C6H12O6, the process by which plants convert carbon dioxide and water into glucose and oxygen using sunlight.

Diffusion

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

Osmosis

The diffusion of water across a semi-permeable membrane from an area of low solute concentration to an area of high solute concentration.

Isotonic Solution

A solution where the concentration of solutes is equal inside and outside the cell, resulting in no net movement of water.

Hypotonic Solution

A solution with a lower concentration of solutes compared to the inside of the cell causing it to swell as water enters.

Hypertonic Solution

A solution with a higher concentration of solutes compared to the inside of the cell causing it to shrivel as water exits.

Symbiosis

A close relationship between two species that benefits at least one of the species involved.

Natural Selection

The process by which organisms better adapted to their environment tend to survive and produce more offspring.

Adaptation

A characteristic that improves an organism's ability to survive and reproduce in its environment.

Biological Diversity

The variety of life in the world, including the variety of species, genetic variations, and ecosystems.

Ecosystem

A community of living organisms interacting with their physical environment.

Metabolism

All the biochemical reactions taking place within a cell.

Enzyme

A biological catalyst that speeds up chemical reactions in living organisms without being consumed.

Photosynthesis

The process by which green plants use sunlight to synthesize nutrients from carbon dioxide and water.

Cellular Respiration

The process of breaking down glucose in the presence of oxygen to produce energy (ATP) for cellular functions.

Endocytosis

The process by which cells take in substances by engulfing them in a membrane.

Exocytosis

The process by which cells expel materials by vesicles fusing with the plasma membrane.

Nitrogenous Wastes

Waste products produced from the metabolism of proteins, which need to be removed to maintain cellular function.