Test part 3 Flashcards
DNA
A nucleic acid that contains the genetic code
4 base pairs and 4 nitrogen bases
Nucleotide
The basic building block of nucleic acids, such as DNA and RNA. It is an organic compound made up of nitrogenous base, a sugar, and a phosphate group
Nitrogenous base
Nitrogen-bearing compound with chemical properties of a base
one of the fundamental components of nucleic acids, such as DNA.
Base pairing rules
Adenine pairs with thymine
Guanine pairs with cytosine
Specific hydrogen bonding in a DNA strand
Helicase
Unzips the DNA strand
DNA polymerase
Reads the DNA strand and adds complementary nucleotides to the new strand
RNA
a long, single-stranded chain of cells that processes protein
Messenger rna (mRNA)
Carries DNA code from nucleus to ribosome, orders tRNA to pickup amino acids
Ribosomal RNA (rRNA)
Assembles ribosomes in nucleus
Transfer RNA (tRNA)
Carries each amino acid to the ribosomes
Transcription
RNA is copied from DNA
Translation
mRNA transcribed from DNA
Protein synthesis
Ribosomes use RNA to assemble amino acids into proteins
RNA polymerase
an enzyme that synthesizes the formation of RNA from a DNA template during transcription.
Ribosome
The site of translation and protein synthesis
Codon
a sequence of three nucleotides that together form a unit of genetic code in a DNA or RNA molecule.
Mutation
Mistakes made when DNA is copied
Changes genetic material of the cell
Duplication
A type of mutation in which a portion of a genetic material or a chromosome is duplicated or replicated, resulting in multiple copies of that region.
Deletion
a part of a chromosome or a sequence of DNA is lost during DNA replication. Any number of nucleotides can be deleted, from a single base to an entire piece of chromosome
Inversion
a segment of a chromosome is reversed end to end. An inversion occurs when a single chromosome undergoes breakage and rearrangement within itself
Translocation
a segment of genetic material from one chromosome becomes heritably linked to another chromosome.
Mitosis
process by which the nucleus divides in eukaryotic organisms, producing two new nuclei that are genetically identical to the nucleus of the parent cell.
PMAT
Meiosis
process by which the nucleus divides in all sexually reproducing organisms during the production of spores or gametes
PMATx2
Gametes
Sex cells
Haploid
Cells that have only one copy of the chromosomes (1n)
Diploid
cells that have two copies of every chromosome (2n)
Chromosomes
Rod-shaped structures made of DNA and proteins called histones
Chromatin
substance of a cell nucleus, consisting of DNA, RNA, and various proteins, that forms chromosomes during cell division.
Independent assortment
When the chromosomes arrange themselves into a random order when they separate
Crossing over
The exchanging of genes between chromosomes to allow genetic variability
Interphase
A period of growth development in the cell cycle
Cytokinesis
The division of a cells cytoplasm (when the cell splits in two)
G1 phase
The longest stage of interphase
The cell is growing and organelles are duplicating
S phase
DNA and chromosomes replicate
G2 phase
Prepares cell for mitosis
Cell continues to grow and checks for errors
Checkpoints
Regulate the cell cycle
Found in interphase, give stop and go ahead signals
Prophase
Chromosomes condense and centrioles move to opposite ends of cell
Metaphase
Chromosomes form a line down the middle
Anaphase
Chromatids separate and move to opposite poles
Telophase
2 new daughter nuclei form
Cleavage furrow
Cells elongate
Mitosis ends
G0 phase
The dormancy period in the interphase or cell cycle in which the somatic cell is resting or dormant
Cancer
A disease in which cells grow and divide uncontrollably, destroying healthy tissue
Heredity
the passing on of physical or mental characteristics genetically from one generation to another.
Trait
a distinguishing quality or characteristic, typically one belonging to a person.
Gene
A portion of a DNA molecule that serves as the basic unit of heredity. Genes control the characteristics that an offspring will have
Allele
one of the possible forms of a gene. Most genes have two alleles, a dominant allele and a recessive allele.
Dominant factor
Stronger, masks recessive
Recessive factor
Seems to disappear
Homozygous
has two of the same allele, whether dominant or recessive,
Heterozygous
having one each of two different alleles
Phenotype
Physical appearance of the individual
Genotype
Alleles an individual receives at fertilization
Complete dominance
The dominant allele will completely mitigate any effect the recessive allele has in determining the outcome of the gene
Incomplete dominance
Offspring are intermediate between two parental phenotypes
Neither allele is completely dominant over the other resulting in 3 phenotypes
Codominance
Both alleles of a gene are expressed
Neither allele is dominant or recessive
sex-linked traits
The genes on the X chromosome that have no matching genes on the Y chromosomes
(Usually recessive)
