Exam 4 Review Flashcards
What occurs during S Phase
Protiens are synthesized
How many homologous pairs of chromosomes does a somatic cell have? how many pares are autosomal and sex chromosomes
23 pairs
22 autosomal pairs, 1 sex pair
Sister chromatiad are joined together by what structure
Centromere
What structure do microtubules come from
centrosome
What are teh 3 purposes of mitosis
1.) growth/development
2.) Replication
3.) asexual reproduction
Does mitosis produce genetically identical or different daughter cells? how many?
2 identical
T/F in anaphase of meiosis, chromosomes separate to opposite poles
TRUE
Name the phases of mitosis in order
Interphase, Prophase, Metaphase, Anaphase, Telophase
What is contact inhibition
Cells stop dividing when they begin to touch
What is the purpose of meiosis
create gametes for sexual reproduction
How many chromomses does a gamete cell have
23
Haploid cell
What happens during Prophase I
Centrioles begin to align and nucleolus/nuclear envelope dissapate
During anaphase I, which structures are being separated
Chromosomes
What is a locus and allele
Locus: location of gene on DNA
Allele: Different versions of genes
Which process does not lead to increased genetic veriability
Crossing over
Mutations
Law of Independent assortment
Law of segregation
Law of segregation
Decribe Mendels 4 hypotheses
1.) Each individual has at least 2 alleles for each trait, one from each parent
2.) the different versions of a trait are containedin 2 inherited alleles
3.) Expression of traits physically is determineed by the genetic info from both parents. An individual obtains one allele from one parent and the other allele from the other parent
4.) THe alleles amy be dominant or recessive
What is nondisjunction
When sister chromatids don’t separate
Wha tis teh genetic make-up of a person affected by Klinefelters Syndrome
XXY
If 2 parets are heterozygous for deafness, what is the phenotype ratio? percentage of carrier? Chance of a deaf offspring?
75% hearing, 25% deaf
50% carriers
25% deaf
What are teh possible gametes for rrYy
rY, ry, rY, ry
What are the possible genotypes for true-breeding parents
YY or yy
What is a test cross
a mating btw an unknown genotype and an homozygous recessive
What is a recessive disorder? Examples? Is a carrier heterozygous or homozygous (5)
Recessive disorder is when a disorder is presented when there is a homozygous recessive gene that creates a disorder
Carrier is someone who has one of the recessive genes affected (heterozygous)
R/G colorblindness, Albinoism, Cistic fibroisis, Tay-Sachs, sickle cell
What is a dominant disorder? Examples? Are there carriers?
Disorder that is carried in the Dominant Gene and expressed when a person is heterozygous
No Carriers
Achondroplasia (Dwarfism), Alzhimers, Huntingtons, Polydactyly
What is incomplete dominance
When a dominant allele is not fully dominant so some of the recessive gene is shown
What is Pleiotrophy. Examples
1 gene controls multiple characteristics. Sickle cell
what is polygenetic inheritance? example
Multiple genes affect 1 thing, eye/hair/skin color
What are sexlinked genes
genes carried on sex chromosomes, usually x, usually recessive
Down syndrome: Genetic make up, Monosomy or Trisomy, # of chromosomes, Autosomal or Sex chromosome
Genetic make up: Extra 21st chromosome
Trisomy
47 chromosomes
Autosomal
Klinefelter syndrome: Genetic make up, Monosomy or Trisomy, # of chromosomes, Autosomal or Sex chromosome
Genetic make up: XXY
Trisomy
47 of chromosomes
Sex chromosome
Turner syndrome: Genetic make up, Monosomy or Trisomy, # of chromosomes, Autosomal or Sex chromosome
Genetic make up: XO
Monosomy
45 of chromosomes
Sex chromosome
Metafemale syndrome: Genetic make up, Monosomy or Trisomy, # of chromosomes, Autosomal or Sex chromosome
Genetic make up: XXX
Trisomy
47 of chromosomes
Sex chromosome
Super male syndrome: Genetic make up, Monosomy or Trisomy, # of chromosomes, Autosomal or Sex chromosome
Genetic make up: XYY
Trisomy
47 of chromosomes
Sex chromosome