TTU Biology 1402 Exam 2- Dr. Held
Questions and Answers| Latest
Update
Karyotyping (#chromosome)
-To determine if the patient has an abnormal # of chromosomes
- "A photographic inventory of an individual's chromosomes."
- ordered display of chromosomes, doubled.
Criss- Cross Inheritance
Sons inherit their X chromosome from their mother
Codominance
-The heterozygote expresses both traits (alleles). -"A" and "B" genes make
structures (not enzymes)= sugar types.
-Ex) Blood types (A,B, AB, O)
Multiple Alleles (complication)
- >2 alleles/genes in the population (=more suits/decks of cards).
-Ex. 1: Blood types (3 alleles): A,B,O.
,-EX. 2: Major Histocompatibility complex (MHC) has dozens of alleles-->
tissue/transplant rejections
Epistasis
-One gene masks or "dominates" the effects of another.
-(ex. colour of fur in dogs. BB=black, Bb=black, bb= brown, ee=no pigment-->
yellow)
Polygenic Traits
-One trait is caused by many genes (whose effects are additive).
-Quantitative traits (height, weight, etc.)= often polygenic.
-Ex). Human skin colour: 4 genes. Shades of brown
Pleiotropy
-One gene causes many traits. Ex). Albino mutation--> white hair, pink iris, crossed
eyes
X chromosome inactivation
-Occurs in mammals and leads to Mosaicism (purpose= dosage comp)
mRNA
-Messenger RNA
-Encodes amino acid sequences and carries information into the cytoplasm
, rRNA
-Ribosome RNA
-This and proteins make ribosomes (most abundant kind of RNA)
tRNA
-Transfer RNA
-Interprets codons into proteins
Double Helix
-Shape of DNA found by Watson & Crick in 1953
- a twisted ladder: rungs=base+ base bond, sides =sugar+ phosphate bond.
A2+T or G2+C
Questions and Answers| Latest
Update
Karyotyping (#chromosome)
-To determine if the patient has an abnormal # of chromosomes
- "A photographic inventory of an individual's chromosomes."
- ordered display of chromosomes, doubled.
Criss- Cross Inheritance
Sons inherit their X chromosome from their mother
Codominance
-The heterozygote expresses both traits (alleles). -"A" and "B" genes make
structures (not enzymes)= sugar types.
-Ex) Blood types (A,B, AB, O)
Multiple Alleles (complication)
- >2 alleles/genes in the population (=more suits/decks of cards).
-Ex. 1: Blood types (3 alleles): A,B,O.
,-EX. 2: Major Histocompatibility complex (MHC) has dozens of alleles-->
tissue/transplant rejections
Epistasis
-One gene masks or "dominates" the effects of another.
-(ex. colour of fur in dogs. BB=black, Bb=black, bb= brown, ee=no pigment-->
yellow)
Polygenic Traits
-One trait is caused by many genes (whose effects are additive).
-Quantitative traits (height, weight, etc.)= often polygenic.
-Ex). Human skin colour: 4 genes. Shades of brown
Pleiotropy
-One gene causes many traits. Ex). Albino mutation--> white hair, pink iris, crossed
eyes
X chromosome inactivation
-Occurs in mammals and leads to Mosaicism (purpose= dosage comp)
mRNA
-Messenger RNA
-Encodes amino acid sequences and carries information into the cytoplasm
, rRNA
-Ribosome RNA
-This and proteins make ribosomes (most abundant kind of RNA)
tRNA
-Transfer RNA
-Interprets codons into proteins
Double Helix
-Shape of DNA found by Watson & Crick in 1953
- a twisted ladder: rungs=base+ base bond, sides =sugar+ phosphate bond.
A2+T or G2+C
