Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Biología Humana II > Development and Pregnancy > Flashcards

Development and Pregnancy Flashcards

1
Q

True or false: Life begins as a single cell

A

true; fusion between sperm and ovum. Contains all of the inherited information it needs to grow and develop.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Birth occurs after how many weeks?

A

38 weeks of prenatal growth and development or 40 weeks from beginning of last menstruation.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Primary oocyte undergoes meiosis I to form:

A

secondary oocyte and a polar body, each with 23 chromosomes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

During ovulation a _______ is release from the ovary and travels slowly towards the uterus.

A

secondary oocyte surrounded by granulosa cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Sperm are _________ attracted to the secondary oocyte

A

chemically; Cluster around it and attempt to penetrate the granulosa cells.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

true or false: Sperm swim against the fluid current flowing.

A

true; Prostaglandins assist sperm movement by causing reverse peristalsis of the uterus and uterine tubes.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

true or false: Usually only one uterine tube contains a secondary oocyte

A

true

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

How long is the journey of a sperm

A

takes approx. 1 hour

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Sperms use what to digest a path through the granulosa cells around the secondary oocyte?

A

acrosomal enzymes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

True or false: Once one sperm penetrates the oocyte; Blocks all other sperm from entering

A

true

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Secondary oocyte completes ______ to form _____ and _____

A

meiosis II; ovum and polar body

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

fertilization

A

occurs when the sperm and ovum nuclei fuse to form a zygote

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

zygote

A

first cel of pre-embryo; contains 46 chromosomes 23 from the sperm and 23 from the ovum

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

secondary oocytes are viables for how long after ovulation

A

24 hours

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Sperm are viable for how long

A

72 hours

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

zygote undergoes _____

A

cleavage; Rapid division by mitosis– cell number increases without cell growth.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

morula

A

pre-embryo reaches the uterus; Solid ball of cells not much larger than the zygote

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

blastocyst

A

Contains 2 parts:
1. Embryo blast from which the embryo later develops
2. Trophoblast that helps to form the placenta.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Implantation

A

Blastocyst uses enzymes from the trophoblast to penetrate into the endometrium

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

When does implantation begin and ends?

A

begins approx. 7 after fertilization and completes by 14th day.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Embryonic discs forms from _____

A

embryoblast

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

embryoblast consists of three primary germ layers that form all body tissues and organs:

A
  1. Ectoderm
  2. Mesoderm
  3. Endoderm
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Ectoderm

A

forms nervous system and epidermis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Mesoderm

A

middle layer, forms muscles, bone tissue, blood, and other connective tissues

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Endoderm

A

forms the epithelial lining of digestive, respiratory, and urinary tracts

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Chorion (extraembryonic membrane)

A

Trophoblast becomes the outermost membrane.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Chorionic villi

A

Extensionsoftrophoblastthat have grown into endometrium

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

Amnion (extraembryonic membrane)

A

Forms posterior to the embryo and eventually surrounds it

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

Amniotic cavity

A

space between amnion and embryonic disc, is filled with amniotic fluid

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

Function of amniotic cavity

A

Absorbs shocks

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

yolk sac (extraembryonic membrane)

A

Forms early formed elements and germ cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

function of yolk sac

A

Absorbs shocks and forms primitive gut

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

allantois

A

Forms early formed elements; Brings umbilical blood vessels to placenta

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

allantois and yolk sac form

A

umbilical cord

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

Placenta

A

Disc-shaped structure formed of both embryonic and maternal tissues

33
Q

Embryonic part of placenta contains:

A

formed of the chorion and chorionic villi.

34
Q

Maternal portion of placenta contains:

A

formed of the associated endometrium

35
Q

how many umbilical arteries bring embryonic blood to placenta

A

2

36
Q

how many umbilical veins return blood to the embryo

A

1

37
Q

true or false: does the placenta contain nerves

A

false

38
Q

true or false: Placenta is the interface between the embryonic blood and maternal blood for exchange of materials

A

true; water, respiratory gases, nutrients, wastes, hormones, and antibodies.

39
Q

true or false: embryonic blood and maternal blood mix

A

false

40
Q

Maternal blood vessels open into

A

lacunae

41
Q

Embryonic blood vessels extend into and
branch

A

lacunae

42
Q

What is used to exchange material across embryonic blood vessels?

A

diffusion

43
Q

Offspring during this time is called an embryo

A

3rd- 8th week

44
Q

By the 4th week what is recognizable?

A

head and limb buds

45
Q

By the 7th week what is present?

A

rudiments of all organs are present; eyes and ears are viable.

46
Q

true or false:

A

By the 8th week, the embryo has a distinct human appearance

47
Q

Developing offspring is now called a fetus.

A

9th- (38th -40th week)

48
Q

fetus

A

head is as large as the body and all organs are present

49
Q

9th through 12th weeks

A

Bone ossification occurs and organs continue to develop

50
Q

13th through 16th weeks

A

Eyes and ears reach final positions

51
Q

when can heartbeat be detected?

A

13th through 16th weeks

52
Q

17th through 20th weeks

A

Lanugo (fine hair) covers body and hair is on scalp
Vernix caseosa form
Movements may now be detectable by mother.

53
Q

Vernix caseosa

A

protects the skin from the digestive and urinary wastes in the surrounding amniotic fluid

54
Q

By 20th week, weighs approx

A

1lb

55
Q

21st through 29th weeks

A

Fetus is lean with wrinkled, translucent skin

56
Q

By 29th week, weighs approx

A

3 lbs

57
Q

30th weeks to birth: (8th and 9th months)

A

Deposition of adipose tissue
Descent of testes in males
Lanugo is shed, the skin is pinkish with ample subcutaneous tissue, hair covers the scalp
Organ systems ready for birth

58
Q

30th weeks to birth: (8th and 9th months) fetus weighs about

A

7.5 lb

59
Q

Human chorionic gonadotropin (hCG)

A

produced by the trophoblast and chorion

60
Q

function of Human chorionic gonadotropin (hCG)

A

Maintains the corpus luteum for the first 10 to 12 weeks of development; Continues to secrete high levels of progesterone and estrogens to maintain the endometrium

61
Q

when is Human chorionic gonadotropin (hCG) detected by pregnancy tests

A

within 8 to 10 days after fertilization.

62
Q

hCG concentration peaks

A

after approx. 10 weeks of development.

63
Q

Blood hCG level declines and levels off between

A

16 and 20 weeks; Corpus luteum degenerates as a resul

64
Q

true or false :the placenta by approx. 12 weeks, it takes over the role of producing estrogens and progesterone.

A

true; Prevents the loss of the endometrium when the corpus luteum degenerates

64
Q

During pregnancy high blood levels of progesterone

A

suppresses GnRH, which prevents the release of FSH and LH; ovaries remain inactive during pregnancy

65
Q

true or false: Blood levels of both estrogens and
progesterone increase during pregnancy

A

true; Stimulate mammary gland development

66
Q

progesterone inhibits ______ during most of the pregnancy

A

uterine contractions

67
Q

As pregnancy nears full term ______ increases blood concentration

A

estrogens; promote uterine contractions

68
Q

Braxton Hicks contractions

A

False labor

68
Q

Relaxin

A

Secreted by corpus luteum and placenta.
Helps in developing placental blood vessels and other maternal cardiovascular changes

69
Q

Parturition (birth process)

A

occurs within 2 weeks of the calculated due date
Approx. 280 days from the beginning of the last menstruation

70
Q

The fetus is usually ______ at the beginning of labor.

A

head down

71
Q

Longest stage

A

6 to 12 hours

72
Q

First stage of labor

A

dilation of the cervix; Amnion ruptures as cervix dilates

73
Q

Labor Process:

A
  1. Cervical stretching triggers formation of action potential that are sent to the hypothalamus
  2. Hypothalamus activates the posterior lobe of the pituitary to release oxytocin
74
Q

oxytocin

A

stimulates rhythmic contraction of the uterus.

75
Q

First stage of labor

A
  1. Fetus head pushes against cervix, resulting in greater stretching
  2. Causes more action potentials to be sent to the hypothalamus
  3. Hypothalamus causes more oxytocin to be release from posterior lobe
  4. Higher blood oxytocin level stimulates more intense and frequent uterine contractions
76
Q

True or false: the first stage of labor is controlled by a positive feedback mechanism

A

produces increasingly stronger uterine contractions until birth occurs

77
Q

Second stage of labor: delivery of fetus.

A

Lasts less than an hour.
Once the head is expelled, the rest of the body exits rather quickly
Contractions occur every 2 to 3
minutes, lasting about 1 minute

78
Q

Third stage of labor: delivery of the placenta.

A

Caused by continued contractions of the uterus.
Produces some bleeding because endometrial blood vessels at the placental site are ruptured.
Uterine contractions compress broken blood vessels, which reduces bleeding.
Subsequently, the uterus decreases in size rather quickly.

79
Q

Delivery of the placenta

A

Occurs within 15 minutes of the birth of the infant

80
Q

true or false: first breath; Increase in blood CO2 level activates the respiratory rhythmicity center is activated

A

true

81
Q

why is the first breath difficult?

A

lungs are collapsed; once first breath is performed surfactant helps prevent alveolar collapse.

Biología Humana II (10 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions