BIOL 101

Fluid Mosaic Model

Describes the cell membrane as a flexible structure composed of phospholipids, proteins, and carbohydrates.

Selective Permeability

The ability of a cell membrane to regulate the passage of substances across it.

Polar Molecules

Molecules with an unequal distribution of charge, which do not pass freely through the nonpolar interior of the cell membrane.

Nonpolar Molecules

Molecules with an equal charge distribution that can diffuse easily through the nonpolar membrane core.

Osmosis

The diffusion of water across a selectively permeable membrane from higher to lower water concentration.

Facilitated Diffusion

The process by which transport proteins help polar molecules or ions cross the membrane down their concentration gradient.

Simple Diffusion

The movement of molecules from high to low concentration without the need for transport proteins.

Endocytosis

The process of bringing large molecules or substances into the cell.

Exocytosis

The process of exporting large molecules or substances out of the cell.

Phagocytosis

A type of endocytosis that engulfs large particles.

Receptor-Mediated Endocytosis

A type of endocytosis that relies on binding specific molecules.

Characteristics of Living Organisms

Order, reproduction, growth, response to environment, regulation, energy processing, evolutionary adaptation.

Hypothesis-Driven Scientific Studies

Involves formulating a testable hypothesis and designing experiments to test its validity.

Controlled Experiments

Experiments with one manipulated variable for comparison.

Observational Studies

Studies that rely on existing data without manipulating variables.

Organic Macromolecules

Four major categories: carbohydrates, lipids, proteins, and nucleic acids.

Protein Synthesis

The process involving DNA, mRNA, and ribosomes to create proteins.

Enzymes

Biological catalysts that speed up reactions by lowering activation energy.

Kinetic Energy

Energy associated with motion.

Potential Energy

Stored energy based on an object's position or structure.

Energy Transformation

Conversion of energy from one form to another.

Energy Coupling

Using energy from exergonic reactions to drive endergonic reactions.

ATP

A molecule used by cells to store and transfer energy.

Photosynthesis

The process converting light energy into chemical energy in plants.

Cellular Respiration

The process of breaking down organic molecules to release stored energy as ATP.

Redox Reactions

Reactions involving the transfer of electrons, with oxidation and reduction occurring simultaneously.

Oxidation

The loss of electrons from a molecule.

Reduction

The gain of electrons by a molecule.

NAD+

A coenzyme that functions as an electron carrier in cellular respiration.

Glycolysis

The first step of cellular respiration, breaking glucose into pyruvate.

Citric Acid Cycle

The second stage of cellular respiration, further breaking down pyruvate and producing ATP.

Oxidative Phosphorylation

The final stage of cellular respiration generating most ATP.

Hormones

Chemical messengers that coordinate body functions through signaling.

Water-Soluble Hormones

Hormones that cannot pass through cell membranes and bind to surface receptors.

Lipid-Soluble Hormones

Hormones that can pass through cell membranes and bind to internal receptors.

Insulin

A water-soluble hormone regulating glucose uptake in cells.

Glucagon

A hormone that causes the breakdown of glycogen to release glucose into the blood.

Type 1 Diabetes

A condition where the body does not produce sufficient insulin.

Type 2 Diabetes

A condition where insulin is produced but cells are resistant to its effects.

Enzyme Inhibition

Regulation of enzyme activity through inhibitors.

Competitive Inhibition

Inhibition in which an inhibitor competes with the substrate for the active site.

Noncompetitive Inhibition

Inhibition where the inhibitor binds to a site other than the active site, altering the enzyme's shape.

Endocrine Disruptors

Chemicals that interfere with hormonal systems, leading to potential health issues.

Metabolic Disorders

Conditions resulting from abnormal biochemistry, such as diabetes.

Active Transport

Energy-requiring movement of molecules against their concentration gradient.

Facilitated Transport

Transport of molecules across membranes via proteins without energy input.

Coenzyme

An organic molecule that assists enzymes in their activity.

Cell Membrane

A semi-permeable barrier surrounding the cell's interior.

Feedback Mechanism

A process that regulates hormone levels and maintains homeostasis.

Thermal Energy

Energy that results from the movement of particles, often lost as heat.

Homeostasis

The tendency of biological systems to maintain stable internal conditions.

Cellular Homeostasis

The process by which cells regulate their internal environment.