Lab test 2 Flashcards
Steps of binary fission:
Chromosome replicates, cell membrane/wall grows in and pinches off
Centromere:
The middle tightly bound bit
Interphase:
G1, S, G2
Prophase (mitosis):
Chromosomes condense, nuclear envelopes goes away, spindle microtubules begin to form
Telophase (mitosis):
Chromosomes uncoil, nuclear envelope forms
How to tell if diploid/haploid?
How to tell if duplicated/not?
Friend or no?
Sister chromatids or no?
Prophase I (meiosis):
Bivalent form, crossing over occurs
Spindle apparatus activity in meiosis:
Goes away and reforms between telophase I and prophase II
Telophase I vs telophase II:
Haploid number of duplicated chromosomes
vs
Haploid number of single chromosomes
Meiosis in plants:
Diploid sporocytes (cells) in sporangia (organ) form haploid spores
Plant life cycle:
Haploid generation = gametophytes, produces gametes
Diploid generation = sporophyte, produces spores
Most plants are ___-dominant:
Sporophyte
During what parts of its life cycle are plants haploid?
From spore meiosis to fertilization/zygote formation
Animal life cycle:
Only sex cells undergo meiosis
Mitosis vs meiosis:
Diploid, genetically identical VS haploid, genetically different
Principle of dominance:
Offspring resemble only one parent, not a blend of the two parent phenotypes
Principle of segregation/First law:
Alleles of ONE gene segregate independently from one another during gamete formation
Principle of independent assortment/Second law:
Alleles of DIFFERENT genes assort independently from one another during gamete formation
Ratio that results from second law:
9:3:3:1
Monohybrid vs dihybrid:
One characteristic vs two
When do chiasmas form?
Late prophase I
Distance’s effect on chiasmas:
The chance of chiasma formation between a given pair of genes depends on how far apart they are.
How many chromosomes in a human gamete?
22 autosomes, 1 sex chromosome
Disorder - only one X
Turner syndrome
Short stature, broad chest, webbed neck, sterility
Disorder - 3 #21 chromosomes
Down syndrome/trisomy 21
Poor muscle tone, mental developmental delay, almond-shaped eyes, protruding tongue, short limbs/neck
Disorder - 2 Xs
Klinefelter syndrome/XX male syndrome
Small testes, sterility, low testosterone levels, learning disability
Sex-linked recessive traits (examples):
Colourblindness, hemophilia
Types of colourblindness
Protan: reduced red
Deutan: reduced green (more common)
Polygenic traits:
Phenotypic traits that involve contributions from multiple genes. ADDITIVE.
Examples of polygenic traits:
Skin pigmentation, height, IQ, crop yield, milk production in cattle
Study of fingerprints:
Dermatoglyphics
Equation for map units:
of recomb/# total offspring
Biotech:
The use of organisms or their components to make/modify products useful to humans
Traditional biotech:
Selective breeding, yeast in fermentation
Modern biotech:
in vitro manipulation
Forensic biology:
Study of DNA in body tissue/fluid
Requirement for analyzing a sample in forensics:
Samples for study must contain nucleated cells
Steps of forensic analysis:
Extraction, PCR, restriction fragment analysis
Extraction:
Chemically lysing cells to liberate DNA then precipitating it out of solution.
Add cell lysis solution (detergent), add ethanol
How does cell lysis solution work?
Disrupts protein-lipid bonds that compose membranes
How does adding ethanol work?
DNA is soluble in water and insoluble in alcohol
PCR:
Polymerase chain reaction - process that rapidly makes identical copies of any DNA
Ingredients required for PCR:
DNA extract, 4 dNTPs, primers, DNA polymerase
Steps of PCR cycle:
Denaturation - heating to separate strands
Annealing - cool to allow primers to bond to single strands of DNA
Extending - heating to allow DNA pmase to add dNTPs to ends of primers
What’s the cool thing about PCR?
Results in twice the starting quantity
Restriction fragment analysis:
Gel electrophoresis - sequence restriction fragment
DNA has a slightly ___ charge.
Negative
Recombinant DNA:
GMOs (organisms that have acquired genes through artificial protests)
Transgenic organism:
Has genes from another species
Applications of recomb DNA:
cloning, bacteria-killing proteins in cows, disease resistant plants, oilspill-cleaning organisms
