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these are the vocab words you need for the test

active transport

The movement of materials through a cell membrane using cellular energy.

passive transport

The movement of materials through a cell membrane without using energy.


The diffusion of water molecules through a selectively permeable membrane.


The process by which molecules move from an area of higher concentration to an area of lower concentration.

selectively permeable

A property of cell membranes that allows some substances to pass through, while others cannot.


Any substance that cannot be broken down into simpler substances.


Two or more elements that are chemically combined.


Energy-rich organic compound, such as a sugar or a starch, that is made of the elements carbon, hydrogen, and oxygen.


Energy-rich organic compound, such as a fat, oil, or wax, that is made of carbon, hydrogen, and oxygen.


Large organic molecule made of carbon, hydrogen, oxygen, nitrogen, and sometimes sulfur.

amino acid

A small molecule that is linked chemically to other amino acids to form proteins.


A type of protein that speeds up a chemical reaction in a living thing.

nucleic acid

Very large organic molecule made of carbon, oxygen, hydrogen, nitrogen, and phosphorus, that contains the instructions cells need to carry out all the functions of life.


Deoxyribonucleic acid; the genetic material that carries information about an organism and is passed from parent to offspring.


Ribonucleic acid; a nucleic acid that plays an important role in the production of proteins.


compounds that contain carbon


Compounds that don't contain carbon


The process by which cells break down simple food molecules to release the energy they contain.


The process by which cells break down molecules to release energy without using oxygen.

cell cycle

The regular sequence of growth and division that cells undergo.


The stage of the cell cycle that takes place before cell division occurs.


The process by which a cell makes a copy of the DNA in its nucleus.


The stage of the cell cycle during which the cell's nucleus divides into two new nuclei and one copy of the DNA is distributed into each daughter cell.


A doubled rod of condensed chromatin; contains DNA that carries genetic information.


The final stage of the cell cycle, in which the cell's cytoplasm divides, distributing the organelles into each of the two new cells.


A tiny cell structure that carries out a specific function within the cell.


A complex of nucleic acids and proteins, primarily histones, in the cell nucleus that stains readily with basic dyes and condenses to form chromosomes during cell division.


a conspicuous, rounded body within the nucleus of a cell.

nuclear membrane

the double membrane surrounding the nucleus within a cell.


The basic unit of structure and function in living things.


An instrument that makes small objects look larger.

cell theory

A widely accepted explanation of the relationship between cells and living things


the process of grouping things based on their similarities


the study of how living things are classified

binomial nomenclature

The system for naming organisms in which each organism is given a unique, two-part scientific name indicating its genus and species


A classification grouping that consists of a number of similar, closely related species


A group of similar organisms that can mate with each other and produce offspring that can also mate and reproduce


organisms whose cells lack a nucleus

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