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movement of a substance across a cell membrane against its concentration or electrochemical gradient mediated by specific transport proteins and requiring an expenditure of energy
Period of evolutionary change in which groups of organisms form many new species whose adaptations allow them to fill new or vacant ecological roles in their communities.
REQUIRES ENERGY. chemical reactions in which simpler substances are combined to build more complex molecules.
Seeds can form without fertilization; seeds genetically identical to parent- from the male gamete
Generation of offspring from 1 parent occurring w/out gametes fusion, by budding, division of single cell, or of entire organism into 2 or more parts. In most cases, offspring are genetically identical to parent.
(adenine triphosphate) an adenine containing nucleotide triphosphate that releases free energy when its phosphate bonds are hydrolyzed. Energy drives endergonic reactions in cells.
A complex of several membrane proteins that provide a port through which protons diffuse. This complex functions in chemiosmosis with adjacent electron transport chains, using the energy of a hydrogen ion (proton) concentration gradient to make ATP. ATP synthases are found in the inner mitochondrial membrane of eukaryotic cells and in the plasma membrane of prokaryotes.
A method of asexual reproduction by "division in half." In prokaryotes, binary fission does not involve mitosis, but in single-celled eukaryotes that undergo binary fission, mitosis is part of the process.
A type of asexual reproduction in which a new individual develops from outgrowth on the parent.
Second of two major stages in photosynthesis, involving fixation of atmospheric CO2 and reduction of the fixed carbon into carbohydrate
Catabolic reactions(pathway )
metabolic pathway that releases energy by breaking down complex molecules to simpler molecules
An energy-coupling mechanism that uses energy stored in the form of a hydrogen ion gradient across a membrane to drive cellular work, such as the synthesis of ATP. Most ATP synthesis in cells occurs by chemiosmosis.
All the organisms that inhabit a particular area: an assemblage of populations of different species living close enough together for potential interaction
A substance that reduces the activity of an enzyme by entering the active site in place of the substrate whose structure it mimics.
a region along which the density of a chemical substance increases or decreases
An organism that obtains energy and nutrients by feeding on other organisms or their remains.
a kind of allosteric regulation whereby shape change in one subunit of a protein caused by substrate binding is transmitted to all the other subunits, facilitating binding of additional substrate molecules to those subunits
behavior that allows males and females of the same species to recognize each other and prepare to mate
(1) waxy covering that is on the surface of stems and leaves and prevents desiccation of terrestrial plants (2) the exoskeleton of an arthropod made of chitin and protein (3) nematode coat
The synthesis of ATP during photosynthesis, coupled to the cyclic passage of electrons to and from P700, the specialized form of chlorophyll a which is involved in photosystem I, using a series of carrier molecules.
A Network of Microtubules and Interconnected Filaments that extends throughout the cytoplasm and serves a variety of functions : PROVIDE For the SHAPE OF CELLS & ALLOW THE CELL TO BE MOBILE
1. The random movement of molecules or ions or small particles in solution or suspension under the influence of brownian (thermal) motion toward a uniform distribution throughout the available volume; the rate is relatively rapid among liquids and gases, but takes place very slowly among solids.
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