Chapter 3: Genetics, Conception, Fetal development, repro tech

Question 1

Genetics

Answer 1

study of heredity

Question 2

Genomics

Answer 2

the study of genes and their function and related technology

Question 3

genome

Answer 3

an organisms complete set of DNA

Question 4

Genetics vs Genomics

Answer 4

genetics interprets one gene and its structure and role within the body whereas genomics looks at all genes and their interrelationships

Question 5

genotype

Answer 5

genetic makeup

Question 6

phenotype

Answer 6

physical expression of a gene

Question 7

sex-linked inheritance

Answer 7

only males exhibit the disorder because their one X chromosome carries the abnormality, even if the gene is recessive. (includes hemophilia and duchenne’s MD)

Question 8

Risk factors for conceiving a child with a genetic disorder include?

Answer 8

Mother is 35+ years of age. Family hx or pregnancy hx of children with disorder. Parents who have the disorder

Question 9

Carrier Testing

Answer 9

identifies carriers of a recessive disorder and is used when there is a family hx of a genetic condition

Question 10

Preimplantation genetic dianosis (PGD)

Answer 10

detects genetic changes in embryos that are created using assisted reproductive techniques

Question 11

Prenatal testing

Answer 11

used for early detection of genetic disorders such as trisomy 21, hemophilia, and Tay-Sachs disease

Question 12

Newborn screening

Answer 12

detects genetic disorders that can be treated early in life

Question 13

What can nurses do for couples terminating the pregnancy based on genetic testing?

Answer 13

Tell them to anticipate grieving process, encourage communication/sharing of emotions with each other, refer the couple to a support group

Question 14

What can nurses do for couples continuing a pregnancy based on genetic test info?

Answer 14

Give additional info on the genetic disorder. Refer them to support groups with couples experiencing the same situation. Explain that they will grieve over loss of “dream child.” Encourage open communication of emotions.

Question 15

Teratogens

Answer 15

drugs, viruses, infections or other exposures that can cause embryonic/fetal developmental abnormalities

Question 16

The developing human is most vulnerable to the effects of teratogens when?

Answer 16

During organogenesis, which primarily occurs the during 4-8 weeks of gestation.

Question 17

Exposure to teratogens after 13 weeks of gestation may cause?

Answer 17

fetal growth restriction and small organ sizes.

Question 18

Toxoplasmosis

Answer 18

condition caused by toxoplasma, which are protozoa found in cat feces, and uncooked/rare beef/lamb. Toxoplasma can cause fetal death, retardation and blindness.

Question 19

Ovaries

Answer 19

have follicles which contain oocytes and secrete estrogen. Graafian follicles are mature follicles

Question 20

Fallopian tubes

Answer 20

oviducts that surround the ovaries. have fimbriae which pulls the ovum into the fallopian tubes. Peristalsis moves the ovum further along the tubes and into the uterus. Fertilization occurs within the tubes

Question 21

Uterus

Answer 21

pear shaped organ that is the site of implantation and houses the placenta/fetus during pregnancy.

Question 22

Endometrium

Answer 22

inner lining of the uterus that has a basilar and a functional (regenerative) layer. The functional layer thickens in preparation for implantation in response to estrogen/progesterone. If implantation doesn’t occur, the functional layer is shed

Question 23

Ovarian Cycle

Answer 23

cycle that describes the maturation of ova (eggs). Has three phases: follicular, ovulatory, and luteal

Question 24

Follicular phase of Ovarian cycle

Answer 24

First phase of cycle beginning with onset of menstruation and lasts 12-14 days. Luteinizing hormone (LH) and Follicle-stimulating hormone (FSH) direct the maturation of a graafian follicle. The maturing graafian follicle secretes estrogen.

Question 25

Ovulatory Phase of ovarian cycle

Answer 25

Second phase which begins when estrogen levels peak and ends with ovulation (release of oocyte from graafian follicle). LH surges 12-36 hours prior to ovulation, while estrogen levels decrease and progesterone levels increase.

Question 26

Luteal Phase of ovarian cycle

Answer 26

third phase that begins after ovulation and lasts 14 days. The empty follicle forms into the corpus luteum which secretes progesterone and estrogen. If pregnancy doesn’t occur, the corpus luteum degenerates, -> decrease in progesterone, -> menstruation.

Question 27

Endometrial cycle

Answer 27

relates to changes in the endometrial lining of the uterus in response to hormones changing during the ovarian cycle

Question 28

Proliferative phase

Answer 28

first phase of endometrial cycle, which follows menstruation and ends with ovulation. The increased levels of estrogen produced by the graafian follicle cause the endometrium to become thick/vascular to prepare for implantation.

Question 29

Secretory phase

Answer 29

second phase of endometrial cycle that begins after ovulation and ends with menstruation. Endometrium thickens more and the corpus luteum secretes high amts of progesterone. If pregnancy doesn’t occur the endometrium degenerates

Question 30

menstrual phase

Answer 30

third phase of endometrial cycle in which low levels of progesterone (due to pregnancy not occurring) cause the endometrial tissue to slough off.

Question 31

Conception/Fertilization

Answer 31

when a sperm nucleus enters the nucleus of an oocyte. This normally happens in the outer third of the fallopian tube. A zygote is formed and contains the diploid number of chromosomes

Question 32

Monozygotic twins

Answer 32

identical twins; the result of a zygote splitting during the early stages of cell division and forming two identical embryos

Question 33

Dizygotic twins

Answer 33

fraternal twins; the result of two ova being fertilized by two seperate sperm. The fetuses are NOT genetically the same

Question 34

Implantation

Answer 34

embedding of the blastocyte into the endometrium (usually the upper/posterior wall)

Question 35

Embryo

Answer 35

a developing human’s name from the time of implantation to 8 weeks of gestation. (during which organogenesis occurs)

Question 36

Fetus

Answer 36

developing human’s name from week 9 to birth, where organ systems are growing and maturing

Question 37

Umbilical Vein

Answer 37

provides OXYGENATED blood to the fetus

Question 38

Ductus venosus

Answer 38

connects the umbilical vein to the inferior vena cava, where the majority of oxygenated blood enters the right atrium

Question 39

Foramen ovale

Answer 39

opening b/w the right and left atria, where oxygenated blood is shunted to the left atrium. This opening closes after birth due to increased pressure from blood returning to the left atrium (from pulmonary veins)

Question 40

Ductus arteriosus

Answer 40

connects the pulmonary artery with the descending aorta. This opening shunts the oxygenated blood to the aorta.

Question 41

Placenta

Answer 41

formed structure that seperates maternal and fetal blood and prevents mixing. Structure does allow for exchange of gases, nutrients, and electrolytes.

Question 42

Placental hormones

Answer 42

progesterone, estrogen, human chorionic gonadotropin (hCG), and human placental lactogen (hPL).

Question 43

Progesterone (secreted by placenta)

Answer 43

facilitates implantation and decreases uterine contractility

Question 44

Estrogen (secreted by placenta)

Answer 44

stimulates the breasts and uterus to enlarge

Question 45

Human chorionic gonadotropin (secreted by placenta)

Answer 45

stimulates the corpus luteum to secrete estrogen and progesterone until the placenta can do this on its own. Hormone that is assessed in pregnancy tests, rises rapidly during first trimester

Question 46

Human placental lactogen (hPL)

Answer 46

promotes fetal growth, regulates glucose, stimulates breast dvlpmt for lactation.

Question 47

Embryonic membranes

Answer 47

two- chorion and amnion. Chorion (outer) dvlps from trophoblast. Amnion (inner) dvlps from embryoblast. These membranes stretch to allow fetal growth

Question 48

Amniotic fluid

Answer 48

500-600ml composed of water, proteins, carbs, lipids, electros, fetal cells, lanugo and vernix caseosa. Produced by amniotic membrane, then by fetal kidneys is 2nd/3rd trimesters

Question 49

Functions of amniotic fluid

Answer 49

cushion for fetus, prevents fetus from adhering to membranes, space for movement, constant thermal environment

Question 50

polyhydramnios

Answer 50

1500-2000ml, excess amount of amniotic fluid. Increased risk of chromosome/GI/cardiac/neural tube disorders

Question 51

oligohydramnios

Answer 51

<500ml, little amniotic fluid, increased risk of congenital renal probs.

Question 52

Umbilical cord

Answer 52

consists of 2 arteries (carrying deoxygenated blood), and one vein (carrying oxygenated), and wharton’s jelly (prevents compression of vessels)

Question 53

infertility

Answer 53

inability to conceive and maintain a pregnancy after 12 months of unprotected sex. For maintaining pregnancies, more than 3 miscarriages= infertility.

Question 54

Male factors r/t infertility

Answer 54

• endocrine disorders
• spermatogenesis (gonadotoxins like drugs, infections, heat exposure-> inviable sperm)
• sperm antibodies
• sperm transport (structures that block pathway)
• disorders of intercourse (ED, hypospadias..)

Question 55

Female factors r/t infertility

Answer 55

• ovulatory dysfunction (usually ovulation on 14 day)
• Tubal/pelvic pathology (endometriosis, fibroids)
• Cervical factors (cancer, incompetent cervix)

Question 56

RFs for infertility: women

Answer 56

autoimmune conditions, diabetes, eating disorders, malnutrition, excess alcohol or exercise, obesity, older age, STIs

Question 57

RFs for infertility: men

Answer 57

pollutants, radiation, excess alcohol/marijuana/cocaine, impotences, older age, STIs, smoking

Question 58

Basal body temperature

Answer 58

fm takes basal temp each morning and records. Ovulation has occurred if rise in temp by 0.4F for 3 days.