Chapter 3 Definitions Flashcards
Define Homeostasis
A steady internal condition maintained by responses that compensate for changes in the external environment
Define Biotic
Biological. Often in reference to living component of the environment.
Define Abiotic
Nonbiological. Often in reference to physical factors in the environment.
What are the Emergent properties?
What we see as life is the result of atomic interactions and physical processes
What is the Habitable zone?
The specific environment in which a population lives, as characterized by its biotic and abiotic factors.
What are Nucleic Acids?
A complex organic substance present in living cells, especially DNA or RNA, whose molecules consist of many nucleotides linked in a long chain.
What are Lipids?
Organic compounds that are fatty acids or their derivatives and are insoluble in water but soluble in organic solvents.
What is a Polymer?
A macromolecule formed from the bonding together of individual monomers.
What are Monomers?
Identical or nearly identical subunits that link together to form polymers during polymerization
What are Enzymes?
Proteins that accelerates the rate of a cellular reaction by lowering activation energy.
What are Protobionts?
The term given to a group of abiotically produced organic molecules that are surrounded by a membrane or membrane-like structure.
What are Liposomes?
A small spherical sac of phospholipid molecules enclosing a water droplet, especially as formed artificially to carry drugs or other substances into the tissues.
What is DNA?
The large, double-stranded, helical molecule that contains the genetic material of all living organisms.
What is RNA?
A polymer assembled from repeating nucleotide monomers in which the five-carbon sugar is ribose. Cellular RNAs are: mRNA (which is translated to produce a polypeptide), tRNA (which brings an amino acid to the ribosome for assembly into a polypeptide during translation), and rRNA (which is a structural component of ribosomes). The genetic material of some viruses is RNA.
What is Transcription?
The mechanism by which the information encoded in DNA is made into a complementary RNA copy
What is Translation?
The use of information encoded in the RNA to assemble amino acids into a polypeptide.
What are Ribozymes?
An RNA-based catalyst that is part of the biochemical machinery of all cells, they can catalyze reactions on the precursor RNA molecules that lead to their own synthesis.
What is Metabolism?
The biochemical reactions that allows a cell or organism to extract energy from its surroundings and use that energy to maintain itself, grow, and reproduce.
What is an oxidized substance?
A substance that loses energy or an electron.
What is a Reduced substance?
A substance that gains an electron or energy.
What are Stromatolites?
Fossilized remains of ancient cyanobacterial mats that carries out photosynthesis by the water-splitting reaction
What is a Autotroph?
An organism that produces its own food using CO2 and other simple inorganic compounds from its environment and energy from the sun or from oxidation of inorganic substances. Mostly plants and other photosynthetic organisms.
What is a Phototroph?
An organism, typically a plant, that obtains energy from sunlight as its source of energy to convert inorganic materials into organic materials for use in cellular functions such as biosynthesis and respiration.
What is Panspermia?
The theory that life on the earth originated from microorganisms or chemical precursors of life present in outer space and able to initiate life on reaching a suitable environment.
