Ionic Bond
A chemical bond formed by the attraction between oppositely charged ions
Nucleotide
A subunit of DNA or RNA composed of a 5-carbon sugar, a nitrogen-containing base, and a phosphate group
Purines
Have a double ring. Ex: Adenine and Guanine
Pyrimidines
Have a single ring. Ex: Thymine, Cytosine, and Uracil
Bioenergetics
Energy flow and change
Heterotroph
An organism that obtains carbon compounds from other organisms
Autotroph
An organism that forms its own food molecules (carbon compounds) from abiotic materials
Biosphere
The outer portion of Earth-air, water, and soil- where life is found
Entropy
A measure of the degree of disorganization of a system (How much energy in a system has become so dispersed that it is no longer available to do work
Catabolic
A process in which large molecules are broken down into smaller ones
Anabolic
A process in which large molecules are built from small molecules
ADP
(Adenosine Diphosphate) The compound that remains when a phosphate group is removed from ATP, releasing energy
ATP
(Adenosine Triphosphate) A compound that has three phosphate groups and is used by cells to store energy and to fuel many metabolic processes
Prokaryote
An organism whose cells do not have membrane-enclosed nuclei or organelles
Big Bang
When all of our universe's condensed matter exploded, sending it into space where gravity pulled it into planets
Eukaryote
An organism whose cells have a membrane-enclosed nucleus and organelles
Plastid
Synthesize ATP from light in photosynthesis
Chemoautotrophs
An organism that derives energy from the oxidation of inorganic compounds, such as hydrogen sulfide
Photoautotrophs
An organism that derives energy from light and forms its own organic compounds (food) from abiotic carbon sources
Mitochondria
The organelles in eukaryotic cells that carry on cell respiration
Methanogens
Archaebacteria that live in anaerobic environments and produce methane as a by-product of their metabolic process
Virus
A nonliving, infectious particle of nucleic acid, protein, and sometimes, lipid membrane that can replicate only inside a living cell
Anaerobic
Occurring or living in conditions without free or dissolved oxygen
Species
All individuals and populations of a particular type of organism that can interbreed with one another
Lichens
Fungi and algae that live together in close association
Taxonomy
The theories and techniques of describing, grouping, and naming living things
Spontaneous Generation
The belief that a cell can be made from nonliving matter
Cell
The basic living unit
Lysosome
A cell vesicle that contains digestive enzymes (Animals Only)
Endoplasmic Reticulum
Network system of tubes connecting organelles; Smooth (No Ribosomes) + Rough (Has Ribosomes)
Chromosomes
Contain DNA for heredity
Cell Wall
Nonliving, Rigid (Gives Support for Plants Only)
Ribosomes
Small bodies in which proteins are made
Diffusion
The movement of a substance down its concentration gradient from a more concentrated area to a less concentrated area.
Phagocyte
Specialized cell that ingests and destroys foreign particles or microorganisms
Nucleus
Control center for all activity
Nucleoli
Synthesis of RNA
Nuclear Envelope
Double Membrane; Semipermeable
Cytosol
Semifluid material
Cytoplasm
Cytosol + all organelles
Mitochondria
Powerhouse for energy
Cell/Plasma Membrane
Double semipermeable
Golgi Apparatus
Flat sacs that package and secrete molecules for export
Vacuoles
Vesicles for storage of salts, enzymes, food, pigments, H2O; Larger in plants
Contractile Vacuoles
Pumps water in protists
Cytoskeleton
Protein network for shape; Movement is made of microtubules
Extensions of Cytoskeleton
Flagella (Whiplike) and Cilia (Short Hairs)
Chloroplasts
Green plastids for photosynthesis (Plants Only)
Centrioles
Tubelike; For cell reproduction in mitosis (Animals Only)
Abiotic Factors
Referring to a physical or nonliving component of an ecosystem
Producers
An autotroph; Any organism that produces its own food
Food Webs
The overlapping food chains of an ecosystem
Decomposers
An organism that lives on decaying organic material from which it obtains energy and nutrients
Heat Energy
An unusable form of energy for organisms
Enzymes
A protein or part-protein molecule made by an organism and used as a catalyst in a specific biochemical reaction
Free Energy
Energy that is available to do work
Chemical Energy
Energy stored in the structure of molecules
Chemical reactions
The process of building chemical bonds that produces one or more new substances
Synthesis
The process of building chemical compounds from smaller components by means of chemical reactions
Metabolism
The sum of all the chemical changes taking place in an organism
Absorption
When the large intestine reabsorbs water
Ecosystem
A biological community and its abiotic environment
Cancer
A group of disease that involves abnormal, uncontrolled growth and division of cells
Cell Cycle
An ordered sequence of events in the life of a dividing eukaryotic cell, composed of mitosis and interphase growth and DNA synthesis phases
Cell-Cycle Arrest
An abrupt halt in the cell cycle when proteins detect mistakes or damage in DNA that needs to be repaired
Centromere
The specialized region of a chromosome that holds two replicated chromosomal strands together and that attached to the spindle in mitosis.
Chromosome Segregation
Separation of the sister chromatids during mitosis in which each new nucleus receives one copy of each chromosome
Cyclins
A group of proteins whose function is to regulate the progression of a cell through the cell cycle and whose concentrations rise and fall throughout the cell cycle
Cytokinesis
The division of the cytoplasm of a cell after nucleus division
Chromatin
In eukaryotes, the chromosomal material (DNA and associated proteins) as it ordinarily appears in a cell's nucleus with individual chromosomes indistinct