Larsen 3 Flashcards
Eukaryotes
Organisms with internal compartments separated by membranes, enclosed two major parts of cells.
Prokaryotes
Organisms having cells with no internal compartments; ie, single-cell bacteria.
Two major cell parts
Nucleus and cytoplasm
Nucleus
The largest organelle in a cell. It houses one copy of nearly all genetic material, or Dna, of that organism. It is covered by a nuclear membrane, or nuclear envelope, which keeps the contents of the nucleus separate from the rest of the cell.
Cell membrane
A semipermeable membrane surrounding the entire cell. Separating one cell from the next.
Mitochondrion
Considered the “powerhouse” of the cell, because it generates the most energy. The number of mitochondria per cell varies by tissue type and by organism.
Cytoplasm
The fluid that fills the cell and majntains the cells shape. Organelles are suspended in the cytoplasm, which can also store chemical substances. Some Dna is stored in the cytoplasm.
Endoplasmic reticulum
Surrounds the nucleus. It plays and important role in protein synthesis.
Cell wall
Provides a rigid shape and controls the movement of molecules into and out of the cell.
Flagellum
Is a whiplike structure attached to some prokaryotes. Rotated by a motorlike system located in the outer layers of the cell, the flagellum enables locomotion.
Nucleoid region
The genetic material of the prokaryotic cell, but unlike the nucleus of the eukaryotic cell it is not contained within a membrane. A prokaryotic cell has about one-thousandth the genetic material of a eukaryotic cell.
Somatic cells
Also called body cells, comprise most tissues, such as bone, muscles, skin, brain, lung, fat, and hair.
Gametes
Sex cells, sperm in males, and ova, otherwise called eggs, for females.
Genetic code
DNA
Genome
The complete set of genes in an individual cell is called a genome
Homoplasmic
Dna is homolasmic, meaning it is the same in each and every cell.
Mitochondria
Energy producing (ATP) organelles, located in the cells cytoplasm. They posses their own independent dna.
ATP (Adenosine Triphosphate)
A high energy molecule that powers cells and, in turn, powers every tissue in the body.
DNA bases
A-adenine
T-thymine
G-guanine
C-cytosine
Nucleotide
Every unit of sugar, phosphate, and nitrogen base forms a single nucleotide.
Complementary bases
Guanine and cytosine are complementary
Adenine and thymine.
Single nucleotide polymorphism (SNPs)
Variations in the DNA sequence due to the change of a single nitrogen base.
Replication
Somatic cells use mitosis
Gametes use meiosis
Starts with one cell, then multiplies into multiple cells until a full body, where cells are still dying and being replaced
Zygote
Single celled fertilized egg.
Matriline
DNA. Such as mitochondrial DNA, whose inheritance can be traced from mother to daughter or son.
Heteroplasmic
Refers to a mixture of more than one type of organellar DNA. Such as mitochondrial DNA, within a cell or a single organisms body. Usually due to the mutation of the DNA in some organelles but not in others
Heterozygous
The condition in which a pair of alleles at a single locus on homologous chromosomes are different
Homeotic (HOX) genes
Also known as homebox genes, they are responsible for differentiating the specific segments of the body, such as the head, tail, and limbs, during embryological development
Homologous
Refers to each set of paired chromosomes in the genome
Homozygous
The condition in which a pair of alleles at a single locus on homologous chromosomes are the same
Karyotype
The characteristics of the chromosomes for an individual organism or a species, such as number, size, and type.
Law of independent Assortment
Mendel’s Second Law, which asserts that the inheritance of one trait does not affect the inheritance of other traits.
Law of Segregation
Mendel’s Firdt Law, which asserts that the two alleles for any given gene (or trait) are inherited, one from each parent; during gamete production, only one of the two alleles will be present in each ovum or sperm.
Linkage
Refers to the inheritance, as a unit, of individual genes closely located on a chromosome; an exception to the Law of Independent Assortment
Locus
The location of an allele, or gene, on a chromosome
Meiosis
The production of gametes through one DNA replication and two cell (and nuclear) divisions, creating four haploid game tic cells.
Messenger RNA
The molecules that are responsible for making a chemical copy of a gene needed for a specific protein, that is, for the transcription phase of protein synthesis.
Microsatellites
Specific loci in nuclear or organellar DNA that gave repeated units of 1-4 base pairs in length; they can be used in various genetic studies.
Mitochondria
Energy-producing (ATP) organelles in eukaryotic cells; they possess their own independent DNA
Mitosis
The process of cellular and nuclear division that creates two identical diploid daughter cells.
Monosomy
The condition in which only one of a specific pair of chromosomes is present in a cell’s nucleus
Non-coding DNA
Sequences of a gene’s DNA (also known as introns) that are not coded to produce specific proteins and are excised before protein synthesis
Nondisjunctions
The failure of the chromosomes to properly segregate during meiosis, creating some gametes with abnormal numbers of chromosomes.
Nucleotides
The building block of DNA and RNA, comprised of a sugar, a phosphate group, and one of four nitrogen bases.
Adenine
One of four nitrogen bases that make up DNA and RNA; it pairs with thymine in DNA molecules and uracil in RNA molecules
Amino Acids
Organic molecules combined in a specific sequence to form a protein.
Anti-bodies
Molecules that form as part of the primary immune response to the presence of foreign substances; they attach to the foreign antigens.
Anticodon
Sequences of three nitrogen bases carried by tRNA, they match up with the complementary mRNA codons and each designate a specific amino acid during protein synthesis.
Antigens
Substances, such as bacteria, foreign blood cells, and enzymes, that stimulate the immune systems antibody production.
Autosomes
All chromosomes, except the sex chromosomes, that occur in pairs in all somatic cells (not the gametes).
Coding DNA
Sequences of a gene’s DNA (also known a exons) that are coded to produce a specific protein and are transcribed and translated during protein synthesis.
Codominance
Refers to two different alleles that are equally dominant; both are fully expressed in a heterozygote’s phenotype.
Codons
The sequences of three nitrogen bases carried by mRNA that are coded to produce specific amino acids in protein synthesis
Cross-over
The process by which homologous chromosomes partially wrap around each other and exchange genetic information during meiosis
Cytoplasm
The jellylike substance inside the cell membrane that surrounds the nucleus and in which organelles are suspended
Cytosine
One of four nitrogen bases that make up DNA and RNA; it pairs with guanine.
Diploid
A cell that has a full complement of paired chromosomes
Essential amino acids
The amino acids that cannot be synthesized in the body; they must be supplied by the diet.
Eukaryotes
Multicelled organisms that have a membrane-bound nucleus containing both the genetic material and specialized organelles
Free-floating nucleotides
Nucleotides (the basic building block of DNA and RNA) that are present in the nucleus and are used during DNA replication and mRNA synthesis.
Gametes
Sexual reproductive cells, ova and sperm, that have a haploid number of chromosomes and that can unite with a gamete of the opposite sex to form a new organism.
Genome
The complete set of chromosomes for an organism or species that represents all the inheritable traits.
Genomics
The branch of genetics that studies species genomes
Haplogroups
A large set of haplotypes, such as the Y-chromosome or mitochondrial DNA, that may be used to define a population.
Haploid
A cell that has a single set of unpaired chromosomes, half of the genetic material.
Haplotypes
A group of alleles that tend to be inherited as a unit due to their closely spaced loci on a single chromosome.
Heritability
The proportion of phenotypic variation that is due to inheritance rather than to environmental influence.
Heteroplasmic
Refers to a mixture of more than one type of organellar DNA, such as mitochondrial DNA, within a cell or a single organisms body, usually due to the mutation of the DNA in some organelles but not in others.
Heterozygous
Refers to the condition in which a pair of alleles at a single locus on homologous chromosomes are different
Homeotic (HOX) genes
Also known as homeobox genes, they are responsible for differentiating the specific segments of the body, such as the head, tail, and limbs, during embryological development.
Homologous
Refers to each set of paired chromosomes in the genome
Homoplasmic
Refers to nuclear DNA, which is identical in the nucleus of each cell type (except red blood cells).
Paleogenetics
The application of genetics to the past, especially in anthropology and paleontology; the study of genetics in past organisms.
Patriline
DNA whose inheritance can be traced from father to daughter or son, such as the Y chromosome, which passes from father to son.
Peptide bond
Chemical bond that joins amino acids into a protein chain
Polygenic
Refers to one phenotypic trait that is affected by two or more genes.
Polymerase chain reaction (PCR)
A technique that amplifies a small sample of DNA into a larger amount that can be used for various genetic tests.
Polymorphism
Refers to the presence of two or more separate phenotypes for a certain gene in the population
Polypeptide
Also known as a protein, a chain of amino acids held together by multiple peptide bonds.
Recombination
The exchange of genetic material between homologous chromosomes, resulting from a cross-over event.
Regulatory genes
Those genes that determine when structural genes and other regulatory genes are turned on and off for protein synthesis
Regulatory proteins
Proteins involved in the expression of control genes
Replication
The process of copying nuclear DNA prior to cell division, so that each new daughter cell receives a complete complement of DNA
Ribonucleic acid (RNA)
A single-stranded molecule involved in protein synthesis, consisting of a phosphate, ribose sugar, and one of four nitrogen bases.
Ribosomal RNA (rRNA)
A fundamental structural component of a ribosome.
Ribosomes
The orgnelles attached to the surface of endoplasmic reticulum, located in the cytoplasm of a cell; they are the site of protein synthesis.
Sex chromosomes
The pair of chromosomes that determine an organisms biological sex.
Single nucleotide polymorphism (SNPs)
Variations in the DNA sequence due to the change of a single nitrogen base.
Structural genes
Genes coded to produce particular products, such as an enzyme or hormone, rather than for regulatory proteins
Structural proteins
Proteins that form an organisms physical attributes.
Thymine
One of four nitrogen bases that make up DNA; it pairs with adenine
Transcription
The first step of protein synthesis, involving the creation of mRNA based on the DNA template.
Transfer RNA (tRNA)
The molecules that are responsible for transporting amino acids to the ribosomes during protein synthesis.
Translation
The second step of protein synthesis, involving the transfer of amino acids by tRNA to the ribosomes, which are then added to the protein chain
Translocations
Rearrangements of chromosomes due to the insertion of genetic material from one chromosome to another
Triplets
Sequences of three nitrogen bases each in DNA, known as codons in mRNA.
Trisomy
Refers to the condition in which an additional chromosome exists with the homologous pair.
Uracil
One of four nitrogen bases that make up RNA; it pairs with adenine
Zygote
The cell that results from a sperm’s fertilization of an ovum.
