Biology Basics and Cytology

This flashcard set covers the basic concepts of biology, the principles of evolution (natural and artificial selection), and detailed cytology including cell theory and organelle functions.

Biology

The study of life.

Characteristics of Life

Metabolism, reproduction, growth, movement, responsiveness, and complex organization.

Scientific method

A methodology based on the observation of phenomena to formulate hypotheses that are both testable and falsifiable; used to test hypotheses, collect data, and analyze data statistically.

Evolution

The concept that all organisms are related to each other by common ancestry; it is the unifying theme in biology.

Natural selection

A mechanism formulated by Charles Darwin and Alfred Wallace for evolution based on the survival of offspring best adapted to their conditions, who then pass their genes to the next generation.

Artificial selection

The process where humans select traits in an organism's offspring, such as in pets or farm crops.

Cytology

The study of cells.

Cell Theory

The principle that all living things are composed of cells and come from cells.

Cell size regulation

Cells remain small to maximize the ratio of surface area to volume for regulating the internal cell environment.

Cell (plasma) membrane

Composed of a fluidlike phospholipid bilayer, proteins, cholesterol, and glycoproteins.

Cell wall

A structure outside the cell membrane composed of carbohydrates like cellulose (plants) or chitin (fungi), or carbohydrate derivatives like peptidoglycan (bacteria).

Cytoplasm

Material outside the nucleus that serves as a site for metabolic activity.

Cytosol

A solution with dissolved substances such as glucose, $CO_2$, $O_2$, etc.

Organelles

Membrane-bound subunits of cells with specialized functions.

Cytoskeleton

A supportive and metabolic structure composed of microtubules, microfilaments, and intermediate filaments.

Prokaryotic Cells

Cells with a simple cellular organization containing no nucleus or other membrane-bound organelles.

Eukaryotic Cells

Cells with a complex cellular organization containing membrane-bound organelles inside the cell membrane.

Nucleus

Contains DNA in the form of chromosomes and controls cellular activities via genes.

Nucleolus

A site located within the nucleus responsible for ribosome synthesis.

Rough endoplasmic reticulum

Organelle that has ribosomes and is necessary for protein synthesis.

Smooth endoplasmic reticulum

Organelle lacking ribosomes that is primarily involved in lipid synthesis.

Golgi apparatus

A packaging center for molecules that also synthesizes carbohydrates.

Lysosome

Contains hydrolytic enzymes for intracellular digestion.

Peroxisome

Involved in the synthesis and degradation of hydrogen peroxide ($H_2O_2$).

Chloroplast

The site of photosynthesis.

Chromoplast

An organelle that contains nongreen pigments.

Leukoplast

An organelle used to store starch.

Mitochondrion

Produces adenosine triphosphate (ATP).

Vacuole

A general storage and space-filling structure within the cell.