ch 2: prenatal development Flashcards
zygote
the single cell formed from seperate spem and egg cells at conception
ovum
the cell released monthly from a woman’s ovaries, which, if fertillized, forms the basis for the developing organism
fallopian tube
the tube between the ovary and the uterus down which the ovum travels to the uterus and in which conception usually occurs
uterus
the female organ in which the embryo/fetus devlops(popularly reffered to as the womb)
sperm
the cells produced in a mans testes that may fertilized an ovum following intercoruse
chromosomes
the structures, arrayed in 23 pairs, within each cell in the body that contain genetic information. Each chromosome is made up of many segments called genes
gametes
sperms and ova. These cells, unlike all other cells of the body, contain only 23 chromosomes rahter than 23 paris
deoxiribonucleic acid( DNA)
the chemilcal of which chromosomes are composed
what is a locus?
a gene that controlling or influencing a specific characteristic always appears in the same place. ex: blood type
what is the Human Genome Project (HGP)
a project that has identified every locus of every human gene
autosomes
the 22 chromosomes pairs
sex chromosomes
comes in two variety, referred to as the X and the Y chromosomes
polygenic pattern of inheritance
any pattern of genti transmission in which multiple genes contribute to the outcome, such as is presumed to occur for complex traits such as intelligence or temparent
multifactorial pattern of inheritance
the pattern of gentic transmission in which both genes and environment influence the phenotype
What is genomic imprinting?
in which some genes are biochemically markat the time ova and sperm devlop in the bodies of potential mothers and fathers.
mitochondrial inheritance
chidlren inherit genes located outside the nucleus of the zygote
mitochondria
DNA that is passed from mother- and duaghter
fraternal(dizygotic) twins
children carried in the same pregnancy but develop from two sperately fertilized ova. They are no more alike than other paris of siblings
identical (monzygotic) twins
Children carried in the smae pregnancy who develop from two sperately fertilized ovum. They are gentic clones of each other
germinal stage
the first stage of prenatal devlopment beginning at conception and ending at implantation of the zygote in the uterus (approximately in the first 2 weeks)
blastocys
Name for the mass of cells from roughly 4-10 days after fertlization
embryo
the name given to the developing organism during the period of prenatal devleopment between about 2 weeks and 8 weks after conception, begining with implanatation of the blastocyst in the uterine wall.
embryonic stage
the second stages of prenatal developmet from week 2 through week 8, when embryo’s organs form,
amnion
the sac, or bag, filled with liquid in which the emryo/ fetus floats during prenatal life
chorion
the outer layer of cells of the blastocyst during prenatal devlopment, from which both the plancenta and the umbilical cord are formed
placenta
an organ that develops between the fetus and the wall of the uterus during gestation
umbilical cord
the chord connecting the embry/ fetus to the placenta, ocntaining two arteris and one wein
fetus
the name given to the developing organism from about 8 weeks after birth,
fetal stage
the third stage of prenatal devlopment, from week 8 to birth, when growth and organ refinement take place
What stage do male embryo start to secrete androgens?
4 and 8 weeks, males start to secrete androgens and the hormone responsible to testies
Congenital adrenal hyperplasia
a disorder which the mom has taking a drug. That masculizes the female fetus. resulting in male-like genitalia, and masculized characteristics of behavior.
what is one of the hormones that portect female development
particular testosterone in males
How much faster do girls progress in prenatal development?
4 to 6 weeks
is there a gender difference in wakefulness?
yes male fetus are more awake then females
Is there a sex difference in responsiveness
yes female fetuses repsond more to external stimuli than males
when can a fetus start to physically respon?
at about 25 weeks
when can fetuses start to distinguish stimuli
at 32-33 week they can distnguish between familiar and novel stmuli
at what stage can a fetus start to learn through music?
at about 24-38 weeks fetus learn music/ nursury rhymes
is there a sex difference in female fetsus?
yes gender male difference.
teratogens
substances such as viruses and drugs or events that can cause birth defects
autosomel disorders
are caused by genes located on the autsomes
sex-linked disorder
are found on the X chromosome
phenylketonurie(PKU)
tonxins that build up baby’s brain and cause mental retardation
sikle-cell disease
a deformity of red blood cells, more comon in West african and African Americans
, mediterranean, Carribean, Indian. Arab and Latin american.
Tay-Sachs disease
occurs in about 1 in 3,000 Jewish couples of Eastern european decent. Severe mental retardation, and blindness, very few live past age 8
Huntington’s disease
this disorder causes the brain to deteriorate and affects both psychological and motor functions
hemophilia
a sex linked disorder, affects 1-5,000 boys, where they cannot stop beeding naturally
Trisomy
which a indivdiual have 3 compies of a particular autosome
what is the most sever trisonmy
trisomy 13 and 18
Klinfelter’s syndrom
a sex-chromose anomalie that is caused by a XXY pattern. effects 1 out of 1,000 males. long legs and arms, and underveloped testies
Turners syndrom
girls with XXX pattern, occurs 1 in 3,000 female births, show stunted growth and sterile, usually need hormone therapy to develop breast or menstruate
Downs Syndrom(Trisomy 21)
A gentic anomaly in which every cell contains three copies of chromosome 21 rather than two. Children born with this gentic patter have characteristics physical featus and usually have mental retardation
how many babies are born from women with HIV/AIDS in the US?
6,000
what are antiretroviral drugs?
drugs a mother is susposed to take to lower the risk of HIV/Aids to her baby
Why Do people with HIV/AIDS in africa afraid to tell their parents?
because they fear being stigmatized
What is the most serious sexually transtmitted disease among pregnant women?
cytomegalovirus(CMV) a virus that is in the herpes
What birth effect result from syphillis and gonorrhea
Both cause brain defects. Syphillis causes eye and ear and brain defects. Gonnorhea can cause the infant to be blind
Does diabetes have an effect on the fetus?
yes can cause some developmental delays
what is the effects on cocaine on fetus?
low birth weight and brain damage
what is some of the effect of mirijuanna and heroin of the fetus?
msicarriage, premature labor, and early death
Does over counter medication effect the fetus?
no they can take them on an as-needed basis
what is the dietary increase that mothers need to take while pregnant
adding about 300 calories, more vitamin B and folic acid
How does stress effect pregnant mothers?
emotional and physical stress will increase low birth weight, short changes in fetuses heart beat
what are the 3 stages of fetal development?
germinal –> embryonic—> fetal
Neuronal proliferation
he rapid devlopment of neurons(specialized cells of the nervous system) between the 10th and 18th week of gestiation( neurons started back in week 3)
Neuronal migration
(weeks 13-21) the movement of neurons to specialized regions of the brain. Move as cell bodies
Glial cells
the glue things together
