Biology/Introduction To Biology
Chromatin composed of DNA and proteins, condenses into chromosomes when cell is about to divide
karyotype displays chromosomes
autosomes 22 pairs
interphase period of time between cell divisions
S DNA Synthesis chromosome now composed of 2 sister chromatids
G2 double everything
M phase division of nucleus and cytoplasm
Mitosis most cells undergo, 1 cell division, 2 daughter cells, genetically identical.
prophase - desenigrate
metaphase - all lined up
anaphase - pulled apart
telophase - physical division of cytoplasm
cytokinesis division of cytoplasm
checkpoint delay the cycle until all is well
mutations due to diff. environmental assaults can result in abnormal growth in cells.
angiogensis formation of blood vessels
meiosis formation of cell gametes/sex cells, 2 cell divisions, 4 daughter cells, not genetically identical.
synapsis homologous chromosomes line up side by side
crossing over during synapsis, homologues sometimes exchange genetic material
polypoid eukaryote 3 or more set of chromosomes
aneuploid organism that doesnt have exact multiple of diploid # of chromosomes
monosomy 1 type of chromosome
trisomy 3 type of chromosomes
non disjunction failure of homologues to separate in meitosis
deletion end of chromosome breaks off
duplication certain chromosome segment more than once in same chromosome
translocation movement of chromosome segment to 1 chromosome to another.
mendel (scientist) used pea plants for genetic experiments
examine only 1 trait
TT - Homozygus Dominan
Tt - Heterozygus
tt - Homozygus Recessive
law of segregation each individual has 2 factors for each trait. factors separate during formation of sex cells.
genotype alleles pairing
phenotype physical trait
dihybrid cross true breeding plants differed in 2 traits. 2 possible outcomes.
law of independent assortment independently (w/ out reguard to how the others separate)
rules of probability flipping a coin. no memory
pedigree determine whether a condition is recessive or dominant.
tay-sachs disease - uncontrollable seizures
cystic fibrose - common lethal genetic diseases, thick mucuss
PKU - metabolic disorder, affecting nervous system
sickle cell - heart failure
neurofibromatosis - brown splotches
huntington disease - degeneration of brain cells
achondropasic - dwarfism
heterozygote, intermediate phenotype
both dominant genes are expresed equally
single gene has more than 1 effect
contain only nucleotides molecules that are composed of a nitrogen base, phosphate, A pentose (5 xarbon sugar)
contains deoxyribose C-G. A-T
contains ribose C-G A-U
occurs during S phase in nucleus. process of copying a DNA molecule. each strand unwinds and serves as template for new strand.
each strand is half old and half new
DNA replication steps
complementary base pairing
helicose unzip DNA molecule
DNA polymerose adds complenmentary base pairing, rejoins the DNA molecule
Transcription in nucleus, DNA turn into mRNA
Translation in cytoplasm, mRNA turn into amino acid/polypeptide
splicing introns (non coding) section removed leaving only exons (coding)
alternative mRNA splicing increases possible # of protein products that can be made from a single cell
RNA joins with proteins to form ribosomes
transfer RNA (tRNA) tranfers amino acids to the ribosomes
end binds to correct codon
point mutations change in single DNAa nucleotide, sickle cell
frameshift mutation insertion or deletion of 1 or more nucleotides
reproductive cloning desired end is a individual that is exactly like original
therapeutic cloning desired is mature cells of various cell types that could be used to treat human illness
gene cloning done to produce many identical copies of the same gene
gene pharming use
animals to produce pharmaceuticals. therapeutic and diagnostic proteins
are injected into animals DNA and proteins appear in the animals milk.
xenotransplanation use of animal organs in humans
gene therapy insertion of foreign gene into human cells for treatment of a disorder
coding DNA 2 percent of genome, only exons are incorporated into mRNA
non coding DNA 98 percent of genome. introns intervening sequences or regulators of gene expression.
functional genomics understand the exact role of genome in cells or organisms
proteomics study of structure, function & interaction of cellular proteins.
bioinformatics app. of comp. technologies to the study of biological ....
comparitive genomics compare the human genome to the genome of other organisms
natural selection aspect
within enviroment chooses members of the population w/ the advantages
phenotype to reproduce more than the other members.
components of natural selection
memebers of a population have inheritable variations.
a population is able to produce more offspring than enviroment can support.
only certain members of pop. survive and reproduce.
nat. selection results in a pop. adapted to the local enviroment.
evolution changes in pop. overtime due to the accumulation of inherited diff.
fossils evidence for evolution, traces of past life.
sedimentations recognizable layer in several layers
common ancestor 1 couple can give rise to many descendants
transitional fossil closely related to the common ancestor
homologous structure - anatomically similar, inherited from a recent common ancestor.
analogous structures - no common ancestor, not constructed similarly
comparitive anatomy vertebrate, forelimbs used for flight, swimming.
vestigial structures fully developed in group of organisms but non functional in other groups
SNP why we all look different
biogeography study of plants and animals in diff. places in the world.
gene pool population composed of all alleles in all individuals making up population
hardy - weinburg equilibrium no evolution taking place
nonrandom mating when only certain genotypes or phenotypes mate w/ 1 other
gene flow movement of alleles
genetic drift changes in alleles frequencies in gene pool due to chance
bottleneck affect prevents majority of genotypes from participating in next generation
founder effecf establish new population somewhere else
stabilizing selection intermediate phenotype is favored
directional selection extreme phenotype is favored
disruptive selection 2 or more extreme phenotype is favores
macroevolution requires origin of species
speciation splitting 1 species into 2 or more, or transforming into new species
evolutionary species concept members share distinct evolutionary pathway
polyploidy chromosome # beyond the diploid #