Create an account
Upper chamber of the heart that recieves and holds blood that is about to enter the ventricle
Flap of connective tissue between an atrium and a ventricle, or in a vein, that prevents backflow of blood
Small group of cardiac muscle cells in the right atrium that "set the pace" for the heart as a whole
A large blood vessel in mammals through which blood travels from the left ventricle to all parts of the body except the lungs
Condition in which fatty deposits called plaque build up on the inner walls of the arteries
Straw colored fluid that makes up 55%of blood; consists of about 90% water and 10% of dissolved gases, salts, nutrients, enzymes, hormones, waste products and plasma proteins
Iron containg protein in red blood cells that transports oxygen from the lungs to the tissues of the body
Muscular tube at the end of the gastrovascular cavity, or throat, that connects the mouth with the rest of the digestive tract and serves as a passageway for food and air
Disease in which tissues of the lungs loose elasticity, which makes breathing more difficult
ATP (Adenosine Triphosphate)
One of the principal chemical compounds that living things use to store and release energy
First step in releasing energy of glucose in which a molecule of of gluecose is broken into two molecules of pyruvic acid
Latic Acid Fermentation
Biological process by which sugars such as glucose, fructose, and sucrose, are converted into cellular energy
Second stage of cellular respiration, in which pyruvic acid is broken down into CO2 in a series of energy-extracting reactions
Electron Transport Chain
A series of proteins in which the high-energy electrons from the Krebs Cycle are used to convert ADP into ATP
Large protein that uses energy from H+ ions to bind ATP and a phosphate group together to make ATP
Threadlike structures within the nucleus containg the genetic information that is passed from one generation to the next
First and longest phase of mitosis, during which the chromosomes become visable and the centrioles seperate and take up positions on the opposite sides of the nucleus
Second phase of mitosis, during which the chromosomes line up across the center of the cell
Fourth and final phase of MITOSIS, during which the chromosmes begin to disperse into a tangle of the dense material
process in sexual reproduction in which male and female reproductive cells join to form a new cell
Term used to refer to chromosomes that each have a corresponding chromosome from the opposite-sex parent
Term used to refer to a cell that has a single set of chromosomes, therefore a single set of genes
Process by which the number of chromosomes per cell is cut in half through the seperation of homologous chromosomes in a diploid cell
Process in which homologous chromosomes exchange portions of their chromatids during meiosis
Monomer of nucleic acids made up of a 5-carbon sugar, a phosphate group, and a nitrogenous base
Principle that bonds in DNA can form only between adenine and thymine and guanine and cytosine
Enzyme that "proofreads" new DNA strands, helping to ensure that each molecule is a nearly perfect copy of the original DNA
RNA molecule that carries copies of instructions for the assembly of amino acids into proteins from DNA to the rest of the cell
Process in which part of the nucleotide sequence of DNA is copied into a complemantary strand of RNA
Enzyme similar to DNA polymerase that binds to DNA and seperates the DNA strands during transcription
Process by which individuals that are better suited to their environment survive and reproduce more successfully; also called survival of the fittest
Selection by humans breeding of usefult raits from the natural variation among among different organisms
Struggle for Exsistence
Competition among members of a species among food, living space, and other necessities of life
Survival of the Fittest
Process by which individuals that are better suited to their environment survive and reproduce more successfully; also called natural selection
Descent with Modification
Principle that each living species has descended, with changes, from a species over time
Structures that have different mature forms in different organisms but develope from the same embryonic tissue
Please allow access to your computer’s microphone to use Voice Recording.
Having trouble? Click here for help.
We can’t access your microphone!
Click the icon above to update your browser permissions and try again
Reload the page to try again!Reload
Press Cmd-0 to reset your zoom
Press Ctrl-0 to reset your zoom
It looks like your browser might be zoomed in or out. Your browser needs to be zoomed to a normal size to record audio.
Please upgrade Flash or install Chrome
to use Voice Recording.
For more help, see our troubleshooting page.
Your microphone is muted
For help fixing this issue, see this FAQ.
Star this term
You can study starred terms together