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102 terms


9th Grade
the first stage of mitosis or meiosis in eukaryotic cell division, during which the nuclear envelope breaks down and strands of chromatin form into chromosomes
the stage in mitosis or meiosis in which the duplicated chromosomes line up along the equatorial plate of the spindle
a phase of mitosis and meiosis in which the chromosomes separate
the final stage of mitosis or meiosis, during which a nuclear membrane forms around each set of new chromosomes
division of the cytoplasm during cell division
proteins that regulate the cell cycle
Surface area to volume ratio
Determines a cells efficiency to take in and out nutrients. When a cell is too large it can die from starvation or poisoning from waste. Usually once the cell is to large it will divide.
Cancer Cells
Do not have a properly functioning cell-cycle system; instead, they divide excessively and can invade other tissues of the body - UNCONTROLLED CELL DIVISION
A segment of DNA on a chromosome that codes for a specific trait
a group of similar cells that perform the same function
a structure consisting of several tissues adapted as a group to perform specific functions
organ system
a group of organs that work together to perform body functions
Process by which two daughter cells are formed, each containing the same number of chromosomes. CREATES BODY CELLS
a process in cell division during which the number of chromosomes decreases to half the original number by two divisions of the nucleus, which results in the production of sex cells
Crossing over
exchange of genetic material between homologous chromosomes during prophase I of meiosis
adenosine triphosphate, an organic molecule that acts as the main energy source for cell processes; composed of a nitrogenous base, a sugar, and three phosphate groups
adenosine diphosphate; molecule that ATP becomes when it gives up one of its three phosphate groups
phosphate breaks off
How do cells get energy from ATP?
Photosynthesis equation
6CO2 + 6H2O -> C6H12O6 + 6O2
cell respiration equation
C6H12O6 + 6O2 -> 6CO2 + 6H2O
green pigment in plants that absorbs light energy used to carry out photosynthesis
Light-Dependent Reactions
Set of reactions in photosynthesis that use energy from light to produce ATP and NADPH
light-independent Reactions
set of reactions in photosynthesis that do not require light; energy from ATP and NADPH is used to build high-energy compounds such as sugar; also called the Calvin cycle
in cellular respiration, series of ananerobic chemical reactions in the cytoplasm that breaks down glucose into pyruvic acid; forms a net profit of two ATP molecules
Citric acid cycle
in cellular respiration, series of chemical reactions that break down glucose and produce ATP; energizes electron carriers that pass the energized electrons on to the electron transport chain
Electron transport chain
in cellular respiration the most energy is transported during this process
Final Acceptor
oxygen is called this because it is the last molecule in the electron transport chain to accept electrons. Bonds with H2 and makes water (H2O)
Parts of ATP
adenine, ribose, 3 phosphate group
How much ATP is produced in Glycolysis?
How much ATP is produced in the Citric Acid cycle?
How much ATP is produced in the electron transport chain?
lactic fermentation
A process that supplies energy when there is small or no oxygen. forms 2 molecules of ATP
the branch of biology that studies heredity and variation in organisms
the passing of traits from parents to offspring
homologous chromosomes
chromosomes that have the same sequence of genes, that have the same structured, and that pair during meisosis
physical characteristics of an organism
genetic makeup of an organism
The different forms of a gene.
cell that has half the number of chromosomes as body cells (n)
cell with two of each kind of chromosome; , or 2n, number of chromosomes
sex cells
fertilized egg
law of segregation
Mendel's law that states that the pairs of homologous chromosomes separate in meiosis so that only one chromosome from each pair is present in each gamete
Law of independent assortment
mendel's law that each member of a pair of homologous chromosomes separates independently of the members of other pairs so the results are random
situation in which both alleles of a gene contribute to the phenotype of the organism
incomplete dominance
creates a blended phenotype; one allele is not completely dominant over the other
multiple alleles
three or more forms of a gene that code for a single trait
polygenic inheritance
An additive effect of two or more genes on a single phenotypic character
A chromosomal alteration in which the organism possesses more than two complete chromosome sets. It is the result of an accident of cell division.
sex-linked traits
traits that are dominant or recessive depending on gender, disorder pertinent to gender, ie females cant be colorblind..traits can only be carried or present on X or female gene
Deoxyribonucleic acid; the genetic material that carries information about an organism and is passed from parent to offspring.
Double helix
Spiral-staircase structure characteristic of the DNA molecule
parts of DNA
Phosphate group, nitrogenous base (A, C, T, G), sugar (Deoxyribose)
Phosphate and Sugar
DNA backbone
Ribonucleic acid; a nucleic acid that plays an important role in the production of proteins.
type of RNA that carries instructions from DNA in the nucleus to the ribosome
type of RNA that carries each amino acid to a ribosome during protein synthesis
type of RNA that makes up the major part of ribosomes
(genetics) the organic process whereby the DNA sequence in a gene is copied into mRNA. IN NUCLEUS
the process of converting the information in a sequence of nitrogenous bases in mRNA into a sequence of amino acids in a protein. IN RIBOSOMES
Point Mutation
a mutation in which only one nucleotide or nitrogenous base in a gene is changed
Frameshift mutation
a mutation, such as the insertion or deletion of a nucleotide in a coding sequence, that results in the misreading of the code during translation because of a change in the reading frame
the loss of a part of DNA from a chromosome
A mutation involving the addition of one or more nucleotide pairs to a gene.
(genetics) a kind of mutation in which the order of the genes in a section of a chromosome is reversed
change to a chromosome in which a fragment of one chromosome attaches to a nonhomologous chromosome
3.4 billion years ago
when did the geological time scale begin?
Name for the time in earths early history that accounts for ninety percent of earth's time, but only cellular organisms lived. BACTERIA
an era occurring between 570 million and 230 million years ago, characterized by the advent of fish, insects, and reptiles
An era with the Triassic, Jurassic and Cretaceous periods from 251 to 65.5 M years ago, marked by dinosaurs, gymnosperms and angiosperms, as well as the mass extinction at the end of the period. First BIRDS
noting or pertaining to the present era, beginning 65 million years ago and characterized by the ascendancy of mammals. HUMANS
length of time required for half of the radioactive atoms in a sample to decay
miller and urey
Experiments suggested how mixtures of the organic compounds necessary for life could have arisen from similar compounds present on a primitive Earth
sidney fox
American scientist who created protocells by heating amino acids.
spontaneous generation
the idea that living things come from nonliving things (Disproven).
theory that living things come only from other living things
Redi's experiment
proved that maggots do not spontaneously generate from deteriorating meat.
Enables species to blend with it's surroundings
enables one species to resemble another
homologous structures
similar structures that related species have inherited from a common ancestor
analogous structures
structures that do not have a common evolutionary origin but are similar in function
vestigial structures
structures once necessary in ancestral forms, but no longer needed today
adaptive radiation
evolution from a common ancestor of many species adapted to diverse environments
the formation of new species as a result of evolution
divergent evolution
when two or more species sharing a common ancestor become more different over time
stabilizing selection
natural selection that favors the average individuals in a population
The theory that evolution occurs slowly but steadily
directional selection
occurs when natural selection favors one of the extreme variations of a trait
convergent evolution
the process by which unrelated species become more similar as they adapt to the same kind of environment
disruptive selection
natural selection that favors individuals with either extreme of a trait
punctuated equilibrium
a theory of evolution holding that evolutionary change in the fossil record came in fits and starts rather than in a steady process of slow change
gene pool
the combined genetic information of all members of a particular population
genetic drift
The gradual changes in gene frequencies in a population due to random events
allelic frequency
percentage of any specific allele in a populations gene pool
gene flow
movement of alleles into or out of a population due to the migration of individuals to or from the population
walking upright on two legs
The division of organisms into groups, or classes, based on specific characteristics
the science of describing, naming, and classifying organisms
evolutionary history of a species
classification based on common ancestry
binomial nomenclature
a system for giving each organism a two-word scientific name that consists of the genus name followed by the species name
diagram that shows the evolutionary relationships among organisms based on derived characters; resembles a timeline