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11 Cards in this Set

  • Front
  • Back
Where can you find genetic differences?

What are identical twins called?

what is the ratio?

___zygote(s) and what occurs?

what are faternal twins called?

what is the ratio?

how many zygotes?

why incr. in rate?

percentage of incr. fraternal twin births in the US, and from what time?

why incr?
monozygotic twins

4 in 1,000

one zygote

split during early embryonic development
-1 sperm/1 egg

Dizygotic twins

12 in 1,000

two zygotes

in vitro fertilization

52%/ 1980-97

fertility clinics/implanting more than one blastocyst (early stage of an embryo)=successful pregnancy
Somatic Cells-
___sets of____________(______)



two/ chromosomes/ dipliod

46/ chromosomes

maternal/ 23

paternal/ 23
consists of what?
egg (ovum)
one set of chromosomes (haploid)
23 chromosmes in human gametes
formation of what?

what is involved?

from what to what?

which is called?

in humans, what to what?

process of producing what?
the formation of gametes


diploid to haploid


46 chrom to 23 chrom

two sets (2n) to one set (n)

what is independent assortment?

what is the possible gamete combination?

possible zygote combo?

likelihood of two sibs (not identical twins) to be born genetically identical?

what is this process based on?
paternal and maternal sets of chroms are freely mixed

2^23=8.38 million

70 trillion

less than 1 in 70 trillion

random paternal and maternal
Gregor Mendel-
what did he do?

pub of paper?

what was his law on?
experiment w/ garden peas


genetic inheritance
how do christmas island land crabs reproduce?
females lay 100,000 eggs each breeding season

directly into ocean

each egg is genetically unique

caused by?

alteration of DNA sequences

UV light, radiation, chemicals

sequence of amino acids-building blocks of protein
Cystic Fibrosis-
what occurs?

what do the CF proteins normally do?

what happens to the CF protein?
alveolar cells (lung air sac) are covered w/ mucus

regulates the passage of salts through the cell memb.

CF gene is mutated
Tays-Sachs Disease-
what is it?

what happens?

the lack of what results in what?

what is the cause?
metabolic disorder

gene/ mutated to prod. an abnormal enzyme

lack of enzyme results in the accumulation of fatty cmpds in the brain

destruction of brain cells

1 defective letter
diff from chimps?

earth pop?


# of human nuerons?

life on earth?

what elems, percentage?
frontal lobe/ grossly enlrged

6.5 billion

23.5 degrees

hundred bill to trill nuerons

3.5 billion

C, H, O/ 95%