A segment of DNA on a chromosome that codes for a specific trait
condensed threads of genetic material formed from chromatin as a cell prepares to divide
long strands of DNA found in the eukaryotic cell nucleus; condense to form chromosomes
two daughter strands of a replicated chromosome joined at the middle by a centromere
region where two sister chromatids are joined tightly together
the regular sequence of growth and division that cells undergo
cell grows, performs its normal functions, and prepares for division; consists of G1, S, and G2 phases
the stage of the cell cycle during which the cell's nucleus divides into two new nuclei and one copy of the dna is distributed into each daughter cell
first and longest phase of mitosis, during which the chromosomes become visible and the centrioles separate and take up positions on the opposite sides of the nucleus
the stage in mitosis or meiosis in which the duplicated chromosomes line up along the equatorial plate of the spindle
the stage of meiosis or mitosis when chromosomes move toward opposite ends of the nuclear spindle
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
fanlike microtubule structure that helps separate the chromosomes during mitosis
small region of cytoplasm adjacent to the nucleus
chromosomes that have the same sequence of genes, that have the same structured, and that pair during meisosis
of a cell or organism having two sets of chromosomes or twice the haploid number
of a cell or organism having a single set of chromosomes
(genetics) cell division that produces reproductive cells in sexually reproducing organisms
structure containing 4 chromatids that forms during meiosis
The pairing of replicated homologous chromosomes during prophase I of meiosis.
process in which homologous chromosomes exchange portions of their chromatids during meiosis
random distribution of homologous chromosomes during meiosis
A picture of all the chromosomes in a cell arranged in pairs
diffusion of water through a selectively permeable membrane
describes a solution whose solute concentration is higher than the solute concentration inside a cell
describes a solution whose solute concentration is lower than the solute concentration inside a cell
when the concentration of two solutions is the same
the path molecules travel when an imbalance between separated molecule concentrations exists
transport of a substance across a cell membrane by diffusion
the process by which a cell membrane surrounds a particle and encloses the particle in a vesicle to bring the particle into the cell
the process by which a substance is released from the cell through a vesicle that transports the substance to the cell surface and then fuses with the membrane to let the substance out
small membrane sacs that specialize in moving products into, out of, and within a cell
a type of nucleic acid that is capable of replicating and determining the inherited structure of a cells proteins
Basic units of DNA molecule, composed of a sugar, a phosphate, and one of 4 DNA bases
five-carbon sugar that is a component of DNA nucleotides
a functional group consisting of a phosphorus atom covalently bonded to four oxygen atoms
the purines (adenine and quanine) and pyrimidines (thymine, cytosine and uracil) that comprise dna and rna molecules
nitrogen base found in DNA and RNA; pairs with thymine in DNA and with uracil in RNA
The base that pairs with Cytosine in DNA
a base found in DNA (but not in RNA) and derived from pyrimidine
The base that pairs with Guanine with DNA
nitrogenous bases that have a double ring of carbon and nitrogen atoms such as adenine and guanine
nitrogenous bases that have a single ring of carbon and nitrogen atoms, such as cytosine and thymine
a chemical bond that involves sharing a pair of electrons between atoms in a molecule
weak chemical bond formed by the attraction of positively charged hydrogen atoms to other negatively charged atoms
two strands of nucleotides wound about each other; structure of DNA
enzyme involved in DNA replication that joins individual nucleotides to produce a DNA molecule
genetic makeup of an organism
(RNA) single-stranded nucleic acid that contains the sugar ribose
a five-carbon sugar present in RNA
Nitrogen base that pairs with adenine in RNA.
process in which part of the nucleotide sequence of DNA is copied into a complementary sequence in RNA
enzyme similar to DNA polymerase that binds to DNA and separates the DNA strands during transcription
RNA molecule that carries copies of instructions for the assembly of amino acids into proteins from DNA to the rest of the cell
sequence of DNA that is not involved in coding for a protein
expressed sequence of DNA; codes for a protein
part of ribosome that binds to mRNA
the subunit which secondarily binds with mRNA and the other ribosomal subunit to begin translation
type of RNA molecule that plays a structural role in ribosomes
type of RNA molecule that transfers amino acids to ribosomes during protein synthesis
holds the tRNA carrying the next amino acid to be added to the chain
one of a ribosome's three binding sites for tRNA during translation. It holds the tRNA carrying the growing polypeptide chain.
a specific sequence of three adjacent bases on a strand of DNA or RNA that provides genetic code information for a particular amino acid
group of three bases on a tRNA molecule that are complementary to an mRNA codon
AUG; the codon that begins all RNA.
UAA, UAG, UGA
idea that all living things are composed of cells, cells are the basic units of structure and function in living things, and new cells are produced from existing cells
photograph of the view through a microscope
a tiny cell structure that carries out a specific function within the cell
a thin membrane around the cytoplasm of a cell
a part of the cell containing DNA and RNA and responsible for growth and reproduction
a jellylike fluid inside the cell in which the organelles are suspended
strong layer around the cell membrane in plants, algae, and some bacteria
cell that has a nucleus and other membrane-bound organelles
cell lacking a nucleus and most other organelles
process by which molecules tend to move from an area where they are more concentrated to an area where they are less concentrated
point at which the number of diffusing molecules moving in one direction is equal to the number moving in the opposite direction
selectively permeable membrane
A membrane that keeps out some molecules but allows others to pass through
movement of specific molecules across cell membranes through protein channels
energy-requiring process that moves material across a cell membrane against a concentration difference
A double membrane that surrounds the nucleus in the cell
a small round body of protein in a cell nucleus
an internal membrane system in which components of cell membrane and some proteins are constructed
stack of membranes in the cell that modifies, sorts, and packages proteins from the endoplasmic reticulum
cell organelle that stores materials such as water, salts, proteins, and carbohydrates
cell organelle filled with enzymes needed to break down certain materials in the cell
organelle found in cells of plants and some other organisms that captures the energy from sunlight and converts it into chemical energy
the organelles in which nutrients are converted to energy
(adenosine triphosphate) main energy source that cells use for most of their work
straight, hollow tube of proteins that gives rigidity, shape, and organization to a cell
solid rod of protein, thinner than a microtubule, that enables a cell to move or change shape
whiplike tails found in one-celled organisms to aid in movement
short structures projecting from a cell and containing bundles of microtubules that move a cell through its surroundings or move fluid over the cell's surface
particle made up of nucleic acid, protein, and in some cases lipids that can replicate only by infecting living cells
a virus that infects bacteria
(genetics) the process whereby DNA makes a copy of itself before cell division
(genetics) the process whereby genetic information coded in messenger RNA directs the formation of a specific protein at a ribosome in the cytoplasm
The removal of noncoding portions (introns) of the RNA molecule after initial synthesis.
(genetics) any event that changes genetic structure
physical or chemical agent that causes mutations
process in which a single cell or set of cells produces offspring that inherit all their genetic material from one parent.
process in which genetic material from two parents combines and produces offspring hat differ genetically from either parent.
stage of cell cycle when a cell is actively dividing
disk containing cell wall material that develops in plant cells during cytokinesis, eventually dividing the cell into two daughter cells.
mass of cells that remain at their original site.
mass of abnormal cells resulting from uncontrolled cancer cell division.
disease caused by serve disruption of the mechanisms that normally control the cell cycle
spread of cancer cells beyond their original site in the body
one of two chromosomes of the 23rd pair of human chromosomes, which determine an individuals gender
egg or sperm sex cell that contains a single set of chromosomes, one from each homologous pair.
the fusion of the nuclei and cytoplasm of a haploid sperm cell and haploid egg cell, forming a diploid zygote.
diploid cell formed when the nucleus of a haploid sperm cell fuses with the nucleus of a haploid egg cell.
Rod shaped bacteria
spiral shaped bacteria
An organism that requires an extreme environment in which to flourish; some exist in environments with extremely high temperatures or in extremely salty environments.
archaea bacteria that live in very salty environments
an organism that has adapted to living in very high temperatures (heat), such as bacteria or algae
small particle in the cell on which proteins are assembled; made of RNA and protein
rough endoplasmic reticulum (rough ER)
endoplasmic reticulum that is studded with ribosomes on its cytosolic side because of its involvement in protein synthesis.
smooth endoplasmic reticulum (smooth ER)
No ribosomes attached; mainly producing lipids.
a protein carbohydrate compound found in bacterial cell walls
type of asexual reproduction in which an organism replicates its DNA and divides in half, producing two identical daughter cells
hollow tubes used to move cells or exchange DNA between bacteria by conjunction
a natural process resulting in the evolution of organisms best adapted to the environment
a pliable sheet of tissue that covers or lines or connects organs or cells of animals
any of various compounds composed of fatty acids and phosphoric acid and a nitrogenous base
a double layer of phospholipids that makes up plasma and organelle membranes
a solution in which water is the solvent
In the phospholipid bilayer, which part of the phospholipid molecules face the watery inside and the watery outside of the cell?
a protein located in the cell membrane that helps move specific substances in and out of the cell
a molecule in which all atoms have the same electronegativity and the electron distribution is equal
having a pair of equal and opposite charges
a particle that is electrically charged (positive or negative)
a carrier protein that uses ATP to actively transport sodium ions out of a cell and potassium ions into the cell