Key defentions Flashcards
Plasma
Colourless fluid part of the body where fat is suspended
Glycocalyx and example
Outer covering secreted outside the cell wall by some bacteria; protects cell from adverse conditions
EX: traps water and protects the cell from dehydration
Gene
a unit of hereditary information that contributes to the inherited characteristics or traits of an organism; composed of a specific organized sequence of DNA
Cytosol
fluid portion of the cytoplasm exclusive of organelles and membranes
Organelle
subcellular structure that has one or more specific jobs to perform in the cell
Cytoskeleton
network of protein filaments in the cytoplasm of a eukaryotic cell; include microtubules, intermediate filaments, and microfilaments
Phospholipid
a lipid containing a phosphate group in its molecule
Desturase
an enzyme that catalyzes the conversion of single bonds to double bonds in fatty acids
Sterol
steroids carrying a hydroxyl group at C-3
Primary Active Transport
Uses ATP
Secondary Active Transport
Uses an electrochemical gradient
electrochemical gradient
determines the direction ions will flow through an open ion channel
symporter
a membrane protein that moves two different molecules across a cell membrane in the same direction
cotransport
a process that moves two different substances across a cell membrane at the same time
zygote
a single-celled organism that is formed when a sperm fertilizes an egg
self-pollination
when pollen is transferred from the same plant to fertilize it
cross pollination
when pollen fertilizes a flower from another plant
Pleiotropy
production of a single gene of two or more unrelated effects
Linkage map
a graph that shows the relative location of genetic markers on a chromosome
reciprocal cross
a breeding experiment that involves crossing two organisms of different traits twice with the sex of the parents reversed in the second cross
antiparallel
parallel but moving or oriented in opposite directions
semiconservative replication model
a mechanism that explains how DNA is duplicated in all known cells
discontinuous replication model
synthesizing a new strand of DNA in a series of short fragments, called Okazaki fragments
mRNA
carry genetic information needed to make proteins
tRNA
Transfer
A link between mRNA and amino acids during synthesis
RNA polymerase
enzyme that copies DNA into RNA in transcription
Promotor
a DNA sequence that initiates the transcription of a gene
Terminators
sequence of nucleotides that signals the end of a gene or operon during transcription
mRNA splicing
changes a precursor mRNA into a mature RNA
Genetic Code
nucleotide triplet of DNA and RNA molecules that carries genetic information
Transcription factor
factor that regulates the rate at which DNA is transcribed into mRNA
Polyadenylation
a process that adds a poly-A-tail to the 3’ end of RNA molecules
Base-Pair Substitution
genetic mutation that occurs when a single nucleotide in a DNA molecule replaced by another
Missense
gene mutation that occurs when single nucleotide change in DNA results in replacement of amino acid in a protein
What is Metabolism?
The sum of an organism’s anabolic and catabolic biochemical reactions
describe a polymer
A large molecule made up of smaller molecules joined together
Name a five-carbon sugar
ribose
Which type of cells are the most numerous in the human body?
eruthrocytes
The best type of microscopy for viewing living cells is
phase contrast
The instrument used to slice thin sections of material for viewing in a microscope is called a
microtome
prokaryotes have a cell wall composed primarily of
peptidoglycan
A scientist wants to examen the detailed structure of pollen grains to identify the time of year the sample represents. Which one of the following instruments would be best?
scanning electron microscope
Which are more closely related on the phylogenetic tree?
a. Bacteria and Archaea
b. Bacteria and Eukaryota
c. Archaea and Eukaryota.
d. All are equally related
e. None of the choices are correct.
archae and eukaryota
Are ribosomes in the nucleus
no
Is the endomembrane system a system of interrelated membranes that are physically connected
no
Where is sarcoplasmic reticulum not found in abundance
liver cells
3 things about glycoproteins
important for cell signaling
found only on cell membranes
processed in the rough ER
3 things that can diffuse through the plasma membrane
oxygen
water
carbon dioxide
when does chromosome nondisjunction happen
anaphase I or II
Where does transcription occur
nucleus
how do vesicles move from the rough ER to the Golgi
motor proteins transport them on microtubule tracks
thermodynamics
Physical science that deals with the relations between heat and other forms of energy
Entropy
measure of a systems thermal energy per unit of temperature that is doesn’t do useful work
spontaneous reaction
a reaction in which the reactants in a given set of conditions are transformed into products without external influences or energy input
Enthalpy
the measure of energy in a thermodynamic system
Reactants
a substance that takes part in and changes during a reaction
free energy (ΔG)
a thermodynamic quantity tot eh capacity of a system to do work
concentration gradient
a difference in the concentration of a substance from one place to another
Equilibrium
a state in which opposing forces are balanced
exergonic reaction
a metabolic or chemical process accompanied by the release of energy
endergonic reaction
reaction that requires energy and is absorbed in the form of work
catabolic pathway
series of biochemical reactions that break down complex molecules into simpler ones
anabolic pathway
chemical reaction that build complex molecules from simpler ones, while using energy
energy coupling
using energy produced by one reaction to power another reaction
coupled reaction
chemical reaction where two reactions are linked together with one reaction releasing energy to drive another
activation energy
minimum quantity of energy which reactants posses in order to undergo certain reactions
Catalyst
chemical substance that increases the rate of a chemical reaction without undergoing permanent chemical change
transition state
the point where there is a maximum value of energy
Substrate
a medium where chemical reactions occur
enzyme-substrate complex
a temporary molecule formed when the substrate binds to an enzyme
cofactor
a substance other than the substrate which is essential for enzyme activity
rate of enzyme activity increases with
an increase in the concentration of the enzyme
pH optimum:
pH at which a substance like an enzyme functions best
temperature optimum:
Temperature at which something functions best
Combustion
rapid chemical combination of a substance with oxygen producing heat and light
electron carrier
small molecule that transfers electrons from one molecule to another
intermembrane space
area between two or more membranes in a cell
Matrix
material in plant and animal cells (in a specific part of the mitochondria
substrate-level phosphorylation
metabolic reaction that produces ATP or GTP
oxidative phosphorylation
cellular respiration process that uses glucose energy to produce ATP
Fermentation
break down of sugars and other organic material into simpler compounds
anaerobic respiration
cells break down sugars to generate ATP without oxygen
accessory pigments
light absorbing compounds that increase the range of light wavelengths used in photosynthesis
photosystem I
moves electrons across the thylakoid membrane
photosystem II
uses light energy to split water molecules releasing oxygen and electrons into ETC
antenna complex and other name
(light harvesting complex) proteins and light-sensitive pigments that absorb light energy and transfers in into the reaction center
reaction centre
protein complex in chloroplasts that converts light energy into chemical energy
