Honors Biology Vocab

Biology

The study of life

Cell

The smallest unit of life that can carry out all life processes

Unicellular

Organisms made up of a single cell

Multicellular

Organisms made up of many cells

Homeostasis

The ability of an organism to maintain stable internal conditions despite external changes

Metabolism

the combination of chemical reactions through which an organism builds up or breaks down materials

Stimulus

a signal to which an organism responds

Carbohydrates

A type of nutrient that provides energy;includes sugars and straches

Lipid

A type of fat or oil that stores energy and makes up cell membrane

Protein

A molecule that is made up of amino acids that helps build and repair tissues and perform other functions

Monomer

A small molecule that can join with others to form a polymer

Polymer

A large molecule made of repeating monomers

Nucleic Acid

Molecules like DNA and RNA that store and transmit genetic information

Animo Acid

The building blocks of proteins

Nucleotide

The building block of a nucleic acids like DNA and RNA

Enzyme

A protein that speeds up chemical reactions in the cell (nature's catalyst)

Catalyst

A substance that increases the rate of a chemical reaction without being consumed

Activation Energy

The energy required to start a chemical reaction

Covalent Bond

A type of bond where atoms share electrons

Hydrogen Bond

A weak bond between a hydrogen atom and an electronegative atom

Denature

The process of altering the structure of a protein, usually making it nonfunctional

pH

A scale that measures how acidic or basic a solution is

Acidic

Having pH less than 7, indicating more hydrogen ions

Basic

Having a pH greater than 7, indicating fewer hydrogen ions

Chemical Reaction

A process where substances interact to form new substances

Reactants

Substances that start a chemical reaction

Products

Substances formed as a result of a chemical reaction

Cell Theory

The theory that all living things are made of cells, cells are the basic units of life, and cells come from other cells

Prokaryote

A simple cell without a nucleus, like bacteria

Eukaryote

A complex cell with a nucleus, like plants and animal cells

Cytoskeleton

The network of protein fibers in a cell that helps it maintain shape and support

Endoplasmic Reticulum

A network of membranes in a cell that helps with protein and lipid synthesis

Nucleus

The part of a cell that contains genetic material and controls cell activities

Membrane

The protective outer layer of a cell that controls what enters and leaves

Phospholipid

A lipid molecule that is a major component of cell membranes

Golgi Apparatus

An organelle that modifies, sorts, and packages proteins and lipids for delivery

Chloroplast

The organelle in plant cells where photosynthesis occurs

Mitochondrion

The organelle that produce produces energy (ATP) for the cell

Microfilament

Thin, thread like proteins in the cytoskeleton that supports cell structure and movement

Microtubule

Tubular structures in the cytoskeleton that help with cell shape and division

Lipid Bilayer

The double layer of phospholipids that make up the cell membrane

Semipermeable

A property of membranes that allows some substances to pass through but not others

Diffusion

The movement of molecules from an area of high concentration to an area of low concentration

Osmosis

The diffusion of water through a semipermeable membrane

Active Transport

The movement of molecules across a cell membrane using energy

ATP (adenosine triphosphate)

The main energy carrier in cells

Substrate

The substance on which an enzyme acts

Hydrophobic

Repelling water; usually referring to non-polar substances

Hydrophilic

Attracting water; usually referring to polar substances

Equilibrium

A state where the concentrations of substances are equal are both sides of a membrane

Solute

A substance that is dissolved in a solution

Glucose

A simple sugar that is an important energy source of all cells

Endocytosis

The process of taking materials into a cell by engulfing them in the cell membrane

Exocytosis

The process of expelling materials from a cell by vesicles fusing with the membrane

Passive Transport

The movement of molecules across a cell membrane without the use of energy

Facilitated Diffusion

The movement of molecules through a cell membrane via specific transport proteins

ATP

Compound used by cells to store and release energy

Heterotroph

Organism that obtains food by consuming other living things

Autotroph

Organism that is able to capture energy from sunlight or chemicals and use it to produce its own food

photosynthesis

The process by which plants make their own food by using sunlight, water, and carbon dioxide

Chemosynthesis

The process of making food using chemical energy, not sunlight

Pigment

Light absorbing molecule used by plants to gather the sun’s

Chlorophyll

Principle pigment of plants and other photosynthetic organisms

Thylakoid

Sac like photosynthesis membranes found in chloroplasts

Stroma

Fluid portion of the chloroplast;outside of the thylakoid

NADPH

Carrier molecule that transfers, high energy electrons from chlorophyll to the other molecules

Light dependent reaction

Set of reactions in photosynthesis that use energy from light to produce ATP and NADPH

Light independent reactions

Set of reactions and photosynthesis that do not require light; also called the Calvin cycle

Photosystem

Cluster of chlorophyll and proteins found in silo

ATP synthase

Enzyme that crosses over the cell membrane and allows hydrogen ions to pass through it

Calvin cycle

Lights independent reactions of photosynthesis in which energy from ATP is used to build high energy compounds such as sugar

Respiration

The process of breaking down food to release energy, usually involving oxygen

Fermentation

A metabolic process that produces energy without oxygen. *Also makes alcohol

Aerobic

Process that requires oxygen

Anaerobic

Process that does not require oxygen