Lecture 1 Flashcards
Individual first recognized albinism is an inhertable trait
Archibald Garrod
Oculocuaneous albinism type 2 is due to
a defect in the OCA gene on chromosome 15…. different types of albinism, happens on certain chromosome.
a complete set of genetic instructions for any organism
RNA or DNA
coding system for genomic information very smiliar among organisms.
genome
Genome is made up of
RNA or DNA…. coding system for genomic information very similar among organisms..
Transmission Genetics
Encompasses basic principles of heredity and how traits are passed from one generation to the next
Molecular genetics
concerns the chemical nature of the gene itself and how genetic information is encoded, replicated and expressed
population genetics
explores the genetic composition of groups of individual members of the same species and how that composition changes geographically and with the passage of time. It is fundamentally the study of evolution
Early theories related to inheritance
Pangensis, inhertance of acquired characteristcs, preformationism, blending inheritance….. Why are each of them flawed??
developed by Gree philosophers…. specific particles (gemmules) carry inforamtion from vaious parts of the body to repoductive organs, from which they are passed to the embryo….
Pangenisis
Primarily made famous by Lamarch… Traits acquired in a person’s lifetime become incorporated into that person’s hereditary information and are passed on to offspring
inheritance of Acquired Characteristics
Preformationism
Individuals were already pre formed, in egg or sperm, ovist vs spermist…. homonculus.
Blending Inheritance
Offspring are a blend of parental traits
genetic material itself blends
once blended, genetics differences cannot be sperarted out in future generations….. male or female, clearly not blended
germ plasm theory
correct, all cells contian a complete set of genetic information
cell theory
correct, all life is composed of cells, and cells arise only from cells
mendelian inheritance
correct, traits are inherited in accord with defined principles
model organisms,
be familiar w each of these organism as we progress
properties,
why do they studies help us understand
Drosphila melanogaster Escherichia coli Caenorhabditis elegans Arabidopsis thaliana Mus musculus Saccharoyces cerevisiae neurospora crassa zea rerio xenopus laevia
Why are these animals desireable
?
Easy to contain, reproduce quickly, easy to manipulated,
model gnetic organism
… oranisms with hcaracteristics that make them useful for genetic analysis,
Common characteristics of model organisms
- short generation time
- production of numerous progeny
- controlled genetic crosses
- reared in a lab
- numerous
- lg body of knowledge about genetic system
What are some of the implications of all organisms having similar genetic systems?
. That all life forms are genetically related
. That reserach findings on one organisms gene efunciton can often be applied to other organism
. that genes from one organism can often exist and thrive in another organism…
ALL the above….
Look at questions at end of chapter.
2 types of cells
eukaryotic and prokaryotic
what is a fundamental unit of heredity
gene
what come from multiple forms called alleles?
gene
genes confer
phenotype
genetic information is carrried by
RNA and DNA
genes are located
on chromosomes
chromosomes are seperateee through
the process of mitosis and meiosis
Permanent changes in genetic information that can be passed from one cell to another or from parent to offspring
mutations
some traits are affected by
multiple factors
evolution is
a genetic change
gene
inherited determinant of the phenotype
elements that control triats
located at a specific position on a chromosome referred to as a locus
the smallest genetic unit that exhibits the cis-trans position effect(=gene)
allele
alternate form of a gene
phenotype
the observable attributes of an organism;
some things can not be obsereved with the eyes… it may need a chemical analysis
genotype
the genes that an organism posses
chromosomes
the form of genetic material in viruses and cells;
circle of DNA in prokaryotes
DNA or RNA molecule in viruses
A linear nucleoprotien complex in eukaryotes
flow of genetic information
classical… DNA –>RNA–> Protein…. not always like this.
Evolution
The change over time… changes in genetic composition… phenotype change
Chromatin
condensed chromosomes…. colored substance.
Histones
H1 raps and forms beaded chain. limit accessibility of enzymes and other proteins to copy and read DNA. enable DNA to fit within the nucleus . must be seperated for genetic informaiton to be accessed
Origins of replicaiton
Where DNA is being replicated, the two strands split and base pairing starts…
Prokaryotes
Eubacteria, and Archaea…Cells that doe not have a membrane bound nucleus
Eukaryotes
membrane bound nucleus.. .mitochondria… other stuff…
Nucleus in prokaryote
is absent
prokaryote size
1 to 10 um in diameter
prokaryote DNA
circular…
unicellular, no membrane bound organelle
prokaryotes
DNA is closely associated with
histones, to form tightly packed chromosomes
Eukaryotic chromosomes are typically found
in pairs… The two members of a pair share the same loci and are referred to as homologous chromosed
A set of chromosomes cosists of
one member of each pair of chromosomes…
Diploid cells have
two complete sets of chromoses
Haploid (monoploid) cells have
a single complete set of chromosomes
Tetraploid cells have
four complete sets of chromosmes
triploid cells have
three complete sets of chromosomes
centromere
eukaryote. serves as the attachment point for spindel microtubules…
used for chromosome classification…
metacentri- central
submetacentricic- kinda off center
acrocentric- way off center
telocentric. short arm and long arm. at very end… short arm P longQ
A diploid organism has
two sets of chromosomes organized as homologous pairs
Genetic information is transfered from
DNA to RNA to protien
chromatin
DNA + Histones
heterochromotin
tightly folded. can not be transcribed or replicated.
euchromatin
stretched out DNA being used
telomeres
the stable ends of chromosomes, provide stability, limit cell division, play a role in aging and cancer…
centromere
a constricted region of chromosome where the kinetochores form and the spindle microtubules attach
telmerase
…
major functions of mitosis
during embryonic development, mitosis produces a stockpile of cells for embryogenesis
organismal growth occurs through mitotic activity (hyperplasia)
mitosis provieds a mechanism for
the relacement of damaged or worn-out cells
Cell Cycle
…
G1
the cell growth
Go
non dividing
S phase
DNA synthesis, further prep for mitotic division… B cyclins bind to cdc2 kinase. activated MPF leads to activites necessary for mitotis, 2 hrs.
G2
gap phase, 2 hours
M phase
actual mitotic phase… less than an hour
interphase
everything but M phase… Prior to S only 1 chromatic. After 2 chromatid
physical division of nuclear material
karyokinesis
physical division of cytoplasmic material
cytokinesis
karyokinesis is not followed by cytokinessi results in a increase in ploidy,
endomitosis
plodiy
increase in complete sets of chromosomes
