Chapter 2 The Beginnings: From Conception to Birth Flashcards
what chromosome is smaller
Y
how many pairs of chromosomes
23 pairs
what special gene does Y carry
SRY
what does. SRY gene do
activates hormones to grow a penis
Y comes from the
father
Each reproductive cell is called a
gamete
when two gametes combine they create one new cell called a
zygote
what is the only cell In the human body that does not contain all of the persons chromosomes
gamete
genome
entire packet of instructions to make a living organism
allele
any variation within a gene
alleles can be
crucial
epigenegtics
the many aspects of the science of how the environment affects genetic expression
genotype
all the genetic material that the 46 chromosomes carry
inherited and passed down
can you tell the genotype by looking at someone
no
phenotype
actually appearance and manifest behavior of a person
every genotype produces ______ phenotypes
many
methylation
when methyl surrounding each gene enhances, transcribes, connects, empowers, silences, and alters genetic interactions
microbiome
refers to all the microbes that live within every part of the body
copy number variations
genes with repeats or deletions of base pairs
interactions among genes and alleles are often called
additive
* because their effects add up to influence the phenotype
alleles can be
dominant or recessive
a person is called a carrier of the recessive gene when
it is on the genotype but not the phenotype
almost every trait is polygenic
meaning many genes
monozygotic twins
identical
* zygote splits
dizygotic
fraternal
* female released 2 eggs
who are more likely to have two ova released with a cycle
older women
identical twins are always the same
sex
3 stages of prenatal development
germinal
embryonic
fetal
germinal time line
first 2 weeks
embryonic period
3-8
fetal time peroid
8 to birth
2 distinct parts in the germinal phase
shell-placental
nucleus- embryo
first task of the shell is
implantation
day 14 what appears
primitive streak
what is a primitive streak
neural tube
when is it called a fetus
beginning of 9 to birth
age of viability
when a fetus born far too early might survive
what is the age of viability
around 22 weeks
when can the infant recognize the mother
day or two after birth
fontanels
areas on top of newborn head where the skull bones have not yet fused
three chromosomes at particular location
trisomy
3 chromosomes at 13th site
patau syndrome
3 chromosomes at 18th
Edwards syndrome
3 chromosomes at 21 site
down syndrome
Down syndrome middle age at risk for
alzheimers disease
one sex chromosome at 23rd site
turner sundrome
examples of dominant disorders
muscular dystrophy
marfan syndrome
huntingonts
examples of recessive conditions
hemophilia
fragile X sundrime
fragile X syndrome
more than 200 repetitions on one stretch of gene
nurture begins at
prenatal
teratogen
anything that increases risk of prenatal abnormalities and birth complications
* drugs, viruses, pollutants, malnutrition, stress
some teratogens cause damage only during
critical peroid
many teratogens have a threshold effect
virtually harmless until exposure reaches a certain level
drinking can lead to
fetal alcohol syndrome (early)
fetal alcohol effect (later)
folic acid deficient can lead to
spina bifida
low birth weight
under 2,500 grams
being underweight at birth has lifelong consequences including
heart disease, less education, more obesity
what is the most common reason for low birth weight
malnutrition
2nd is drugs
3rd is multiple births
immigrant paradox
newborns of immigrant women tend to be heavier and healthier than those born to native born women of the same SES
two conditions that produce heavier babies
obesity and diabetes
what hormone starts labor
oxytocin
what is considered full term
2 weeks before or after due date
doula
person trained to support laboring woman
* proven helpful to immigrant, low income, unpartnered women
C section
surgical procedure removed through abdomen
newborn health is often measured by
Apgar scale
* color, heart rate, cry, muscle tone, breathing
postpartum depression usually recovers in
6 months
couvade
parental experiences of pregnancy and birth
precent of c section
21%
similar genes humans share
99%
genes
genetic material/DNA which influences some specific aspect of development
chromosomes
organized chain of genes
22 of chromosome pairs are
autosomes
23rd pair of chromosomes are
sex linked
female chromosome
XX
male chromosome
XY
sperm and ova are
gametes
how many chromosomes do gametes have
23
zygote
2 combined gametes
how to determine sex of zygote
whether the fathers Y or X sperm is fertilized
genome
all genetic material
allele
any variation that makes a gene different in some way from other genes for that same characteristic
genotype
genetic inheritance
phenotype
observable characteristics
some of the ways in which nurture influences phenotype
methylation
microbiome
social experiments
single genes
influence specific phenotypes
copy number variations
genes with repeats or deletions of base pairs
proximodistal
growth from areas close to the center of the body to farthest
cephalocaudal
growth from head to tail
downsyndrome site
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