Science Bio Test

Metabolism

All the chemical reactions occurring in the cells of a living organism to maintain life.

Anabolism

The process that builds larger, complex molecules from smaller, simpler ones and requires energy.

Catabolism

The process that breaks down larger, more complex molecules and releases energy.

Enzymes

Organic catalysts that speed up the rate of a reaction without being used up in the process.

Specificity (in enzymes)

The characteristic of enzymes that allows them to attach to a specific reactant molecule due to their particular shape.

Lock and Key Model

Describes how an enzyme's active site has a specific shape that fits a particular substrate, similar to a key fitting into a lock.

Diffusion

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

Role of Enzymes in Digestion

Enzymes change nutrients from food into a form that the body can readily use.

Nutrient Breakdown: Carbs

Carbohydrates are broken down into glucose.

Nutrient Breakdown: Proteins

Proteins are broken down into amino acids.

Nutrient Breakdown: Lipids

Lipids (fats and oils) are broken down into fatty acids and glycerol.

Components of the Circulatory System

Arteries, capillaries, and veins that carry materials to and from every cell in the body.

Pacemaker (SA node)

The part of the heart that initiates the heartbeat.

Heart Rate Control

The heart rate is controlled by the autonomic nervous system and can be influenced by exercise and stress.

Gas Exchange

The process where oxygen diffuses into the bloodstream across the thin walls of the alveoli.

Reactant Molecule

The molecule that is going to be changed by a chemical reaction.

Mitochondria

Organelles where cellular respiration occurs.

Ribosome

The organelle where proteins are manufactured.

Photosynthesis

The process by which green plants and some other organisms use sunlight to synthesize foods with the help of chlorophyll.

Cellular Respiration

The process by which cells convert glucose and oxygen into energy, carbon dioxide, and water.

ATP (Adenosine Triphosphate)

The main energy carrier in cells, produced during cellular respiration.

Biological Catalyst

Substances that increase the rate of a chemical reaction in biological systems without being consumed.

Substrate Concentration

The amount of substrate available for an enzyme to act upon, which affects the rate of enzyme activity.

pH Effect on Enzyme Activity

The measure of acidity or alkalinity, which can influence enzyme structure and function.

Competitive Inhibition

A process where a molecule similar to the substrate competes for the active site of an enzyme.

Non-Competitive Inhibition

A form of enzyme inhibition where an inhibitor reduces enzyme activity regardless of substrate concentration.

Vascular System

A complex network including arteries, veins, and capillaries that transports blood throughout the body.

Hemoglobin

A protein in red blood cells that binds oxygen for transport to tissues.

Chlorophyll

The green pigment in plants that absorbs light energy for photosynthesis.

Anaerobic Respiration

A type of cellular respiration that occurs without oxygen, producing less energy.

Aerobic Respiration

The process that requires oxygen to produce energy from glucose in cells.

Nutrient Breakdown: Nucleic Acids

Nucleic acids are broken down into nucleotides.

Vasoconstriction

The narrowing of blood vessels, which increases blood pressure.

Vasodilation

The widening of blood vessels, which decreases blood pressure.

Affinity (in Enzymes)

The degree to which an enzyme binds to its substrate, affecting the reaction rate.

Feedback Inhibition

A regulatory mechanism where the output of a process inhibits its own production.

Phosphorylation

The addition of a phosphate group to a molecule, often to activate or deactivate enzymes.

Body Temperature Regulation

The process by which the body maintains its core internal temperature.