Term | Definition |
Primary Sex organs | Testes and ovaries |
Secondary sex organs | penis and uterus |
spermatic cord | strand of connective tissue extending from the abdomen to each testicle |
cremaster mucle | surrounds the spermatic cord and contracts in cold weather to draw testes closer to body for warmth |
stored mature sperm remain fertile for.... | 40-60 days |
leydig cells | produce testosterone |
seminiferous tubules | ducts in which sperm are produces, contained in the walls are sertoli cells which promote the development of sperm |
epididymis | where sperm mature and ultimately are stored |
vas deferens | structure that travels from the epididymis through the spermatic cord into the pelvic cavity and over the ureter to the prostate |
onset of puberty triggers the secretion of two gonadotropins.... | FSH and LH |
seminal vesicle | secretes fluid containing semen,frutose, and other substances into ejaculatory duct |
ejaculatory duct | a pair of tubules that pass through the prostate and empty into the urethra |
corpus cavernosa | two large cylinders of erectile tissue that fill the shaft of the penis |
spermatogenesis | begins in the seminiferous tubules |
acrosome | enzymes that help the sperm penetrate the egg during fertilization |
two key qualities of semen include.. | stickiness and alkalinity |
semen stickiness quality | allows semen to stick to the walls of vagina and cervix instead of immediately draining out |
semen alkalinity | counteracts the acidity of vagina |
ovaries | two, about the shape of almonds, sits on each side of the uterus, produce eggs and sex hormones, contains thousands of immature eggs. |
vagina | muscular tube that serves as a receptacle for the penis and sperm |
an embryo.... | attaches to the endometrium of the uterus |
uterus | muscular chamber that houses a growing embryo |
acini | secretes milk during lactation |
the reproductive cycle averages.. | 28 days in length |
ovulation | prompted by spike in LH |
falling levels of estrogen and progesterone trigger.. | menstruation |
hormonal method of birth control | interferes with follicular development and ovulation |
gestation cycle | about 40 weeks |
second trimester | weeks 13 through 24, most of the organs are deeloped |
preembryonic stage | begins when fertilization forms azygote with 46 chromosomes |
morula results | blackberry like cluster of 16 cells, mitotic divisions |
trophoblast | plays key role in ensuring the continuation of an early pregnancy |
amnion | filled with fluid the protects the embryo from trauma and changes in temp. |
embryonic stage begins .... | once germ layers are formed (16 days after conception) |
the umbilical cord contains... | two umbilical arteries and one umbilical vein |
the mothers blood and fetus blood.. | does not mix |
fraternal twins | two placentas |
the placenta also secretes... | estrogen,progesterone, and HCG to maintain the pregnancy |
most of the blood bypasses the liver by... | flowing through the ductus venosus into the inferior vena cava |
the heart begins to beat... | around day 22 |
oxygen-depleted blood flows through the two umbilical arteries to the placenta.... | re-oxygenates it and returns it to the fetus through the umbilical vein |
fetal movement (quickening) can be felt... | week 20 |
the respiratory system, although immature, is capable of gas exchange | at 28 weeks. |
physical changes with pregnancy in circulatory system | increase blood volume by 30-50%, cardiac output increase 30-40% by week 27, as uterus demands more blood supply, heart rate increases also |
probable triggers to labor... | decline in progesterone, release of oxytocin, uterine stretching |
first stage of labor is longest: | 6-18 hours for first time, short for multiple pregancy |
stage two of labor | begins with full dilation of the cervix and ends when the baby is born |
anterior pituitary- prolactin | milk production |
posterior pituitary- ocytocin | milk secretion, causing the lobules in the breast to contract forcing milk into the ducts |
heredity | process of passing traits from biological parents to children |
genetics | the study of inheritance |
genes | segments of DNA |
chromosomes | consist of long strands tightly coiled DNA |
autosomes | chromosomes from mother and chromosomes from father |
female gametes contain only... | X chromosomes |
a child's sex is determined by... | the presence or absence of certain chromosomes |
A child's genetic information | is inherited from both the mother and father |
genome | a complete set of genetic information for one person |
homozygous | person has two alleles that are the same |
heterozygous | if the alleles are different |
for a recessive allele to be expressed, | both chromosomes must carry identical allels |
mutation | a permanent change in genetic material |
autosomal recessive inheritance | children who inherit a single copy of the allele become carriers of the disorder( they cant get it but can pass it on to their children. |
autosomal dominant inheritance | child receives one copy from mother and one from father, child has 50% chance of developing the disorder |