Bio Exam Gabs

Atom

Smallest unit of matter.

Covalent Bond

A bond where atoms share electrons, strong, found in DNA and proteins.

Ionic Bond

A bond where electrons are transferred, weaker in water.

Hydrogen Bonds

Weak bonds that are very important, hold DNA strands together.

Polarity

Uneven charge characteristic of water.

Cohesion

Water sticks to water.

Adhesion

Water sticks to surfaces.

High Specific Heat

Ability of water to stabilize temperature.

pH scale

Ranges from 0 to 14;

Carbohydrates

Macromolecules that provide quick energy and structural support, like cellulose in plants.

Lipids

Macromolecules that provide long-term energy and form cell membranes.

Proteins

Most important macromolecule, responsible for structure, enzymes, and movement.

Nucleic Acids

Macromolecules that store genetic information (DNA & RNA).

Prokaryotic Cells

Cells without a nucleus, such as bacteria.

Eukaryotic Cells

Cells that have a nucleus, such as human cells.

Nucleus

Organelle that stores DNA.

Mitochondria

Organelle that produces ATP (energy).

Ribosomes

Cellular structures that synthesize proteins.

Phospholipid Bilayer

Structure of the cell membrane, selectively permeable.

Passive Transport

Movement of molecules without energy, includes diffusion and osmosis.

Active Transport

Movement of molecules using ATP, against a concentration gradient.

Hypertonic Solution

A solution that causes cells to shrink due to water leaving the cell.

Hypotonic Solution

A solution that causes cells to swell as water enters the cell.

Isotonic Solution

A solution with equal concentration to cytoplasm, causing no net movement of water.

Enzymes

Proteins that speed up chemical reactions by lowering activation energy.

ATP

Adenosine triphosphate, the energy currency of the cell.

Cellular Respiration

Process that converts glucose to ATP.

Glycolysis

The first step in cellular respiration that occurs in the cytoplasm.

Krebs Cycle

The second step of cellular respiration taking place in the mitochondria.

Electron Transport Chain

Final step of cellular respiration that requires oxygen.

Mitosis

Cell division process that produces identical cells.

Meiosis

Cell division that produces gametes with genetic variation.

Mendelian Genetics

Study of how traits are controlled by alleles, including dominant and recessive expressions.

Punnett Squares

Tool used to predict the probability of traits in offspring.

Hardy-Weinberg Equilibrium

Principle that describes population genetics and allele frequencies under stable conditions.

Natural Selection

Mechanism of evolution where the fittest organisms survive and reproduce.

Genetic Drift

Random changes in allele frequencies within a population.

Gene Flow

Movement of genes between populations.

Mutation

Changes in DNA sequence that can lead to variation.

Phenotype

The observable traits or characteristics of an organism.

Steroid Hormones

Lipid-based hormones that can cross cell membranes.

Cell Differentiation

Process by which cells develop different functions from the same DNA.

Cancer

Uncontrolled cell division due to mutations or failure of regulatory mechanisms.

Cell Cycle

The series of events that take place in a cell leading to its division.

Simple Diffusion

Movement of molecules from high to low concentration without energy.

Facilitated Diffusion

Movement of molecules across a membrane through protein channels.

Tonicity

The ability of a solution to change the shape of cells by altering their internal water volume.