Key terms from Chapter 1 Flashcards
Definition of cell theory
The widely accepted explanation of the relationship between cells and living things
Definition of Cell
The basic unit and structure and function of all living things
Definition of organelle
A tiny cell structure that carries out a specific function within a cell
Definition of cell wall
A rigid layer of nonliving material that surrounds the cells of plants and some other organisms.
Definition of cell membrane
A cell structure that controls which substances can enter or leave the cell
Definition of nucleus
A cell structure that contains nucleic acids, the chemical instructions that direct all cells activities.
Definition of cytoplasm
The region between the cell membrane and the nucleus; in organisms without a nucleus, the region located inside the membrane.
Definition of mitochondria
A rod shaped cell structures that convert energy in food molecules to energy the cell can use to carry out its functions.
Definition of endoplasmic reticulum
A cell structure that forms a maze of passageways I which proteins and other materials are carries from one part of the cell to another
Definition of ribosome
A small grain like structure in the cytoplasm of a cell where proteins are made
Definition of Golgi body
A structure in a cell that receives proteins and other newly formed materials from the endoplasmic reticulum, packages them, and distributes them to other parts of the cell
Definition of chloroplast
A structure in the cells of plants and some other organisms that captures energy from sunlight and uses it to produce food
Definition of vacuole
A sac inside a cell that acts as a storage area
Definition of lysosome
A small, round cell structure containing chemicals that break down the food particles into smaller ones
Definition of element
A substance that cannot be broken down into simpler substances
Definition of compound
When two or more elements combine chemically
Definition of carbohydrate
An energy rich compound made of the elements carbon,hydrogen and oxygen
Definition of lipids
Are energy rich compounds made of carbon, hydrogen and oxygen
Definition of proteins
Large organic molecules made of carbon, hydrogen, oxygen, nitrogen and sometimes sulfur
Definition of enzyme
A type of protein that speeds up the chemical reaction in a living thing
Definition of nucleic acids
A very long organic molecule made if carbon, oxygen, hydrogen, nitrogen and phosphorus
Definition of DNA
The genetic material that carries information about an organism and is passed from parent to offspring
Definition of RNA
Ribonucleic acid that plays an important part in the production of proteins
Definition of selectively permeable
( cell membrane is)
That some substances can pass through the membrane while others cannot
Definition of diffusion
( the main method by which small molecules move from the membrane)
Is the process by which molecules move from one area of high con. to a lower area of con.
Definition is osmosis
The diffusion of water molecules through a selectively permeable membrane
Definition of passive transport
The movement of dissolved materials through a cell membrane without using cellular energy
Definition of active transport
The movement of materials through a cell using energy
