Brainscape's Knowledge GenomeTM

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


See full index

Anatomy and Physiology 2B > Human Development and Aging > Flashcards

Human Development and Aging Flashcards

1
Q

What is embryogenesis?

A

Events in development leading up to the embryo

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

The preembryonic stage is___

A

the first 16 days after fertilization

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

What is the fertilization window?

A

egg must be fertilized within 12-24 hours of ovulation

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

What is sperm capacitation?

A

the process that migrating sperm must undergo to make egg penetration possible

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

What are the two important events that occur during capacitation?

A
  • Female fluids leech cholesterol from sperm

- sperm becomes permiable to to Ca2+ increasing powerful flagella movements

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

How long is sperm viable for after ejaculation?

A

6 days

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

What reaction does sperm undergo when it encounters the egg?

A

An acrosomal reaction

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

What is a acrosomal reaction?

A

The exocytosis of the acrosome causing the release of enzymes needed to penetrate the egg

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

Once acrsomoal enzymes clear a path through the granulosa cells the next step is?

A

-sperm binds to the zona pellucida releasing more enzymes to help it to contact the egg

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

Once the sperm contacts the egg?

A

The egg destroys the sperms mitochondria so only the head enters

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

Fertilization is a combination of ___

A

The haploid set from the egg and spem combind

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

When the two haploid sets combine what is the produce?

A

a diploid. Fertilization is complete

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

What is polyspermy?

A

Fertilization of an egg by two or more sperm

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

What two mechanisms prevent polyspermy?

A
  1. Fast block-when sperm binds it opens Na+ channels causing depolarization preventing additional binding
  2. slow block-Penetration by sperm causes inflow of Ca2+ causing a swell of fluid beneth the zona pellucida pushing the rest of the sperm away
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What step occurs after fertilization?

A

-The secondary oocyte completes meiosis II

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

What becomes of the egg and sperms nuclei after fertilization?

A
  • The egg discards one chromatid from each chromosome
  • the sperm and egg swell to become pronuclei
  • pronucli rupture and mix into a single diploid set
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Once a diploid set is formed the egg is now called a ___ and is ready for___

A

Zygote ready for mitotic division

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

____ of all embros die in the first trimester. Why?

A
  • more than 50%
  • Conceptus is most vulnerable at this stage and precautions may not be taken because pregnancy may not have been noticed yet
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What developments occur in the second trimester?

A
  • Most organs complete development
  • Distinct human form
  • Possible to survive if born
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What occurs during the thrid trimester

A
  • Fetus growth is rapid
  • organs can support life
  • birth occurs at end of third trimester
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

When is a fetus considered mature?

A

35 weeks and 5.5 pounds

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

What are the three major processes during the preembryonic stage?

A
  1. Cleavage
  2. Implantation
  3. Embryogenesis
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What is cleavage?

A

mitotic divisions in the first 3 days after fertilization

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

What is implantation?

A

The zygote implants itself into the endometrium

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

What is embryogenesis?

A

the arrangement of the three primary germ layers

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

How many cells are produced during cleavage?

how long is the process of cleavage?

A

about 100 cells in about 72 hours

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

The end result of cleavage is called the___. How long does it rest in the uterus until implantation?

A

Morula?

4-5 days

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

The morula becomes a blastocyst after___

A

The zona pellucida disintegrates and releases the conceptus

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

What is the internal cavity of the blastocyst?

A

The blastocel

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

What is the inner mass within the blastocel?

A

The embryoblast

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

Which portion of the blastocyst becomes the placenta?

A

the outer layer of cells called thee trophoblast

32
Q

Which portion of the blastocyst secretes HCG?

A

The trophoblast

33
Q

The three portions of the blastocyst are_

BTE

A
  • Blastocoel: internal cavity
  • Trophoblast: future placenta
  • Embryoblast: future embryo
34
Q

Implantation occurs when the ____attaches to the _____. This occurs ___ days after ovulation

A

Blastocyst
Placenta
6

35
Q

How does the blastocyst attach to the endometrium?

A

The trophoblast cells that come into contact with the endometrium form two layers and invade the endometrium causing the endometrium to grow over the blastocyst

36
Q

What are the two layers of cells formed by the trophoblast during implantation?

A
  • Syncytiotrophoblast

- Cytotrophoblast

37
Q

What is the function of the syncytiotrophoblast?

A

it is the layer of the trophoblast that invades the endometrium

38
Q

How long does the process of implantation take?

A

about one week

39
Q

What is the first step of embryogenesis?

A

The embryoblast forms an embryonic disc separates into two layers

  • Epiblast
  • Hypoblast
40
Q

After the first seperation what is the next step in embryogenesis?

A

The emergence of three primary germ layers from the embryonic disc.

41
Q

What are the three primary germ layers?

A
  1. Ectoderm
  2. Endoderm
  3. Mesoderm
42
Q

What are the two paces that flank the embryonic disc?

A

The Amniotic cavity and the Yolk sac

43
Q

What is the primitive groove?

A

A split in the epiblast (soon to be sctoderm)

44
Q

What is gastrulation?

A

The process of epiblast cells migrating into the groove and forming replacing the hypoblast with endoderm

45
Q

Inbetween the endoder and the ectoderm forms the____

A

Mesoderm

46
Q

Mesoderm eventually becomes ___

A

Mesenchyme

47
Q

When is Embryogenesis complete

A

Once all three primary germ layers are fully formed

48
Q

Once embryogenesis is complete the zygote is officially a ____

A

Embryo

49
Q

When does the placenta form?

A

6 weeks from the begining of the embryonic stage begins

50
Q

When are nearly all organs present?

A

at 8 weeks

51
Q

Explain the process of embryonic folding

A
  • The flat embryonic disc converts into a cylindrical form
  • The embryo folds around the yolk
  • the ectoderm doubles over and eventually covers the entire embryo
  • The mesoderm splits and forms two layers.
52
Q

What form does the embryo have after the process of embryonic folding

A

A ball with a tube down the middle

53
Q

The ectoderm eventually becomes the ____

A

epidermis

54
Q

the mesoderm eventually becomes the ___

A

connective tissue

55
Q

The endoderm eventually becomes the ___

A

Inner epithelial layers of the digestive tract

56
Q

What are somites?

A

Segmentations of the mesoderm that eventually become the vertebral column, trunk muscles, and the dermis

57
Q

What is the Amnion?

A
  • Amniotic sac
  • a transparent sac that develops from the epiblast
  • completely encloses the embryo
  • penetrated by the umbilical cord
58
Q

What is the yolk sac?

A
  • A sac a fluid that forms from the hypoblast

- contributes to formations of GI tract, blood cells, and future egg and sperm

59
Q

What is the Allantois?

A
  • A pocket that forms from the yolk sack.

- forms the base of the umbillical and part of the bladder

60
Q

What is the chorion?

A

the outtermost embryonic membrane that encloses all of the rest

61
Q

What are the chorionic villi?

A

Pertrusions of embryonic blood vessels that pull nutrients from the mothers blood. Eventually form the placenta

62
Q

What are the three sources of prenatal nutrition?

A
  • Uterine milk
  • Trophoblastic nutrition
  • placental nutrition
63
Q

What is uterine milk?

A

glycogen-rich secretion of the uterine tubes and endometrial glands
-Used for nutrition before implantation

64
Q

What is trophoblastic nutrition.

A

-Nutrition derived from the consumption of endometrium cells.

65
Q

How long does is trophoblastic nutrition used for?

A

Up to 12 weeks but declines as the placenta grows

66
Q

What is the placenta?

A

a disc-shaped organ attached to the uterine wall and to the fetus on the other

67
Q

What is placental nutrition?

A

Nutrients diffused from the mothers blood through the placenta

68
Q

What is the placental stage?

A

The period beginning around 9 weeks until birth where nutrition is supplied by the placenta.

69
Q

What is placentation?

A

The development of the placenta

70
Q

What is contained within the umbilical cord?

A

two umbilical arteries and one umbilical vein

71
Q

What pumps blood from the placenta?

A

The fetal heart

72
Q

Blood returns to the fetus via the

A

umbilical vein

73
Q

An embryo is considered a fetus after ___ weeks

A

8

74
Q

How any circulatory shortcuts are present in the fetus?

A

3

75
Q

The two umbilical arteries form from the ____

A

Internal iliac arteries

76
Q

O2 rich blood flows from the placenta to the _____ via the _____

A

Inferior vena cava

umbilical vein

77
Q

How does the flow of blood differ in the fetus compaired to an infant?

A
  • Blood mostly bipasses the pulmonary circuit

- Passes from atrium to atrium via fossa

Anatomy and Physiology 2B (7 decks)

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