exam

Prokaryotes

Organisms without a membrane-bound nucleus or organelles, smaller than eukaryotes, typically 0.5-5 micrometers, including bacteria and archaea.

Eukaryotes

Organisms with a membrane-bound nucleus and organelles, larger than prokaryotes, typically 10-100 micrometers, including plants, animals, fungi, and protists.

Phylogeny

The evolutionary history and relationships among species.

Taxonomy

The science of classifying and naming organisms.

Three-Domain System

Classification system that divides life into three domains: Bacteria, Archaea, and Eukarya.

Gram-positive bacteria

Bacteria that have a thick peptidoglycan layer and stain purple.

Gram-negative bacteria

Bacteria with a thin peptidoglycan layer and stain pink.

Viral Species

A group of viruses that share common characteristics and can replicate within specific host cells.

Viroids

Small, circular RNA molecules that can cause disease in plants.

Reverse Transcriptase

An enzyme used by retroviruses to convert RNA into DNA for integration into a host genome.

ELISA

Enzyme-Linked Immunosorbent Assay; a laboratory technique to detect and quantify proteins, antibodies, and hormones.

Acellular

Refers to entities like viruses that are not made of cells.

Fungal Spores

Reproductive cells produced by fungi that can develop into a new organism.

Species

A group of organisms that can interbreed and produce fertile offspring.

Strains

Variants within a species that often have slight genetic differences.

Antigens

Substances that induce an immune response, typically recognized by antibodies.

Pathogens

Microorganisms that can cause disease.

Protozoa

Single-celled eukaryotic organisms, such as Giardia and Plasmodium.

Helminths

Parasitic worms, such as Taenia and Ascaris.

Prions

Misfolded proteins that induce misfolding in other proteins, causing diseases.

Photosynthesis

The process by which green plants, algae, and some bacteria convert light energy into chemical energy in the form of glucose, using carbon dioxide and water.

Cellular Respiration

The biochemical process in which cells convert glucose and oxygen into energy (ATP), carbon dioxide, and water.

Mutation

A change in the DNA sequence of an organism that can lead to variations in traits.

Natural Selection

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

Biodiversity

The variety of life in the world or a particular habitat or ecosystem, including species diversity, genetic diversity, and ecosystem diversity.

Ecology

The branch of biology that studies the relationships between organisms and their environment.

Symbiosis

A close and often long-term interaction between two different biological species, which can be mutualistic, commensalistic, or parasitic.

Gene

A sequence of DNA that encodes a functional product, usually a protein, and is the basic unit of heredity.

Chromosome

A structure consisting of DNA and associated proteins that carries genetic information.

Allele

One of two or more versions of a gene that determine distinct traits.

Genotype

The genetic constitution of an individual organism, which may influence phenotypic traits.

Phenotype

The observable physical or biochemical characteristics of an organism, determined by both genetic makeup and environmental influences.

Carbohydrates

Organic compounds made of carbon, hydrogen, and oxygen, which serve as a primary energy source for living organisms.

Proteins

Large molecules made of amino acids that perform a vast array of functions within organisms.

Lipids

Hydrophobic organic molecules, including fats, oils, and steroids, that serve as energy storage, structural components, and signaling molecules.

Nucleic Acids

Biomolecules essential for life, including DNA and RNA, which store and transmit genetic information.

Enzyme

A protein that acts as a biological catalyst, speeding up chemical reactions in the body.

Homeostasis

The tendency of biological systems to maintain stable internal conditions despite external changes.

Evolution

The process through which populations of organisms change over generations through mechanisms such as natural selection.

Antibody

A protein produced by the immune system in response to an antigen, helping to neutralize pathogens.

Vaccination

The act of introducing a vaccine into the body to stimulate an immune response against a specific disease.

Hormone

A signaling molecule produced by glands in the endocrine system that regulates physiological processes.

Stomata

Small openings on the surface of leaves that allow gas exchange (CO2 and O2) and transpiration.

Xylem

Plant tissue responsible for the transport of water and nutrients from roots to leaves.

Phloem

Plant tissue that transports sugars and other metabolic products downward from the leaves.

Fossil

The preserved remains or traces of organisms from the past, often found in sedimentary rock.

Plate Tectonics

The theory that describes the large-scale movements of Earth's lithosphere, which can cause earthquakes, volcanic activity, and the creation of mountains.

Carbon Cycle

The biogeochemical cycle through which carbon is exchanged between the biosphere, geosphere, hydrosphere, and atmosphere.

Nitrogen Cycle

The process by which nitrogen is converted between its various chemical forms, essential for life.

Hydrological Cycle

The continuous movement of water on, above, and below the surface of the Earth.

Climate Change

Long-term alterations in temperature, precipitation, wind patterns, and other elements of the Earth's climate system.

Ozone Layer

A region of Earth's stratosphere that absorbs most of the sun's harmful ultraviolet radiation.

Biomagnification

The increasing concentration of toxic substances in the tissues of organisms at higher levels in a food chain.

Invasive Species

Non-native species that spread widely in a new habitat, often causing ecological harm.