Ch 2 Flashcards
the 3 letters of the DNA alphabet
A C T J
a group of 3 bases is called
codons
genes combine into large rod like structures called
chromosomes
how many pairs of chromosomes do we have
23
how many total chromosomes do we have
46
meiosis creates sex cells called
gametes
germ cells divide into 4 ______ cells
daughter
if a sperm with an X chromosomes fertilizes an egg, the offspring will be a
girl
some differences arise from _____ ,or when parts of chromosomes get rearranged with parts of other chromosomes
translocation
sometimes there are sections of the chromosomes that _____ each other and create new genetic combinations in the new cells
crossover
the only 2 individuals who can share the same chromosomes
identical twins
the other name for identical twins
monozygotic twins
what type of alleles make the effect of any other allele of the same gene
dominant
what type of alleles only show up if both parents pass them on to their child
recessive
what type of alleles are both expressed in a child
codominant
genetic disorders can be dominant, recessive and
sex linked
sometimes geographic and _____ backgrounds make people prone to certain genetic disorders
ethnic
some disorders occur as a result of random errors involving an incorrect number of
chromosomes
who can educate people about genetic disorders before or after pregnancy
genetic counselors
what type of test can doctors run to determine people’s risk factors or current conditions
screening tests
what describes a persons dominant and recessive genes
genotype
a persons location, diet , how they are treated by others, and other factors called
their environment
a persons _____ is the way in which all of a persons traits are expressed
phenotype
development
the origins of the genetic structures that determine embryos
Heredity
transmissions of traits and characteristics from parent to child by genes
genetics
the study of genes or heredity
1 egg meets 1 sperm and 1 zygote splits into 2
monozygotic twins or identical twins
2 eggs meets 2 sperms and share only 50 percent of genetic material
Dizygotic twins or fraternal twins
chance of twins increases
with maternal age or use of fertility drugs
Genetic counseling
addresses chances of genetic abnormalities
Amniocentesis
performed between 14-16 weeks
ultrasound
tracks fetal growth and determines age, sex and structural care