Brainscape's Knowledge GenomeTM

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


See full index

Entrance Biology > Human Reproduction and Development > Flashcards

Human Reproduction and Development Flashcards

You may prefer our related Brainscape-certified flashcards:
AP® Biology flashcards Biology 101 flashcards
1
Q

What are primary sex organs called?

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

Primary sex organs (gonads) in male and female

A
  • testes in males
  • ovaries in females
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What do gonads produce?

A
  • sex cells or gametes
  • steroid hormones called sex hormones
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Accessory reproductive organs

A
  • ducts, glands and external genitalia
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What do testes produce?

A
  • sperm
  • seminiferous tubules produce them in fact
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Location of testes

A
  • within the scrotum – sac of skin and superficial fascia that hungs outside the abdominal cavity at the root of penis
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Midline that divides the scrotum

A
  • septum
  • provides the compartment for each testes
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Male duct system in order

A
  • epididymis, ductus deferens, ejaculatory duct, urethra
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Male accessory glands

A
  • paired seminal glands and a single prostate
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Spermatogenesis

A
  • process in which seminiferous tubules of the testes produce male gametes called sperm or spermatozoa
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

normal chromosomal number in most body cells

A
  • diploid 2n
  • in humans, diploid chromosomal number is 46, containing 23 pairs of chromosomes called homologous chromosomes
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

chromosomes in humans

A
  • 23 pairs
  • homologous chromosomes or homologues
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Number of chromosomes in human gametes

A
  • 23
  • haploid chromosomal number
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What is hormonal control in reproductive system called?

A
  • hypothalamus-pituitary-gonadal axis
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Define pregnancy

A
  • events that occur from the time of fertilization (conception) until the infant is born
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Conceptus

A

Developing offspring in the womb

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

Gestation period

A
  • from last menstrual period until birth
  • approximately 280 days
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Embryonic period

A
  • from fertilization through week 8
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

When is conceptus called an embryo?

A
  • during embryonic period
  • fertilization to week 8
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

When is conceptus called a fetus?

A
  • during fetal period
  • from week 9 through birth
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Fetal period

A
  • from week 9 to birth
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

When does ovum complete meiosis II?

A
  • only when sperm penetrates the oocyte and is finding its way to the nucleus
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

When does fertilization occur?

A
  • when sperm’s chromosomes combine with those of egg (secondary oocyte) to form a fertilized egg (zygote)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

What happens when the sperm enters the oocyte?

A
  • sperm’s plasma membrane is gone
  • sperm uses microtubules to locomote its nucleus towards oocyte nucleus
  • meanwhile, nucleus grows bigger into a male pronucleus
  • secondary oocyte completes meiosis II forming ovum nucleus and second polar body
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

Male pronucleus + female pronucleus

A
  • mitotic spindle develops between them
  • nuclei membranes rupture and chromosomes are released
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

When is the “true” moment of fertilization?

A
  • when maternal and paternal chromosomes combine and produce diploid zygote (fertilized egg)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

Explain “cleavage” period in embryonic development

A
  • mitotic divisions of zygote without intervening growth to increase surface-to-volume ratio for nutrient uptake and waste disposal
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

Cleavage division 36 hours after fertilization

A
  • first division
  • 2 identical daughter cells called blastomeres
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

Cleavage division 72 divisions after fertilization

A
  • cluster of 16 or more cells called morula
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

How many cells does the embryo have after 4 or 5 days of fertilization?

A
  • about 100 cells that accumulate fluid within internal cavity
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

How many days does the blastocyst float in the uterine cavity?

A
  • two to three days
32
Q

How is the blastocyst nourished while floating in the uterine cavity?

A
  • glycoprotein-rich uterine secretions
  • steroid and nutrients like iron and fat-soluble vitamins
33
Q

When does implantation begin?

A
  • six to seven days after ovulation when the endometrium is properly prepared
34
Q

What does the sperm use to approach, bind and enter the oocyte?

A
  • acrosomal enzymes and receptors
  • receptors in oocyte cause the Ca2+ levels within sperm to rise triggering acrosomal reaction
  • enzymes digest holes through zona pellucida of the oocyte
35
Q

How can polyspermy be blocked?

A
  • entry of sperm causes oocyte cytoplasm Ca2+ to rise
  • it triggers cortical reaction that hardens zona pellucida and sperm receptors are clipped off
36
Q

How long does implantation take?

A
  • about 5 days, usually completed 12 days after ovulation
37
Q

How is the viability of corpus luteum maintained?

A
  • hCG secreted by trophoblast cells
  • prompts corpus luteum to continue secreting progesterone and esterogen
38
Q

When is hCG detectable?

A
  • one week after fertilization until end of second month
  • after that, the level falls and reaches a low by 4 months
39
Q

Placenta between 2 and 3 months

A
  • takes over to produce estrogen and progesterone until the end of pregnancy (corpus luteum degenerates)
40
Q

How does the embryo get nutrients before placenta?

A
  • by digesting endometrial cells
41
Q

Function of trophoblast cells

A
  • secret hCG
  • give embryo nutrients
  • develop into placenta
42
Q

Placentation

A
  • formation of placenta
  • cells from original inner cell mass give rise to extraembryonic mesoderm layer that lines the inner surface of trophoblast
43
Q

What is the chorion?

A
  • double-layered membrane formed by the trophoblast and the extra-embryonic mesoderm
  • helps in the exchange of nutrients, gases, and wastes between the embryo and the mother’s body.
44
Q

What is the gastrula?

A
  • blastocyst is being converted into 3 primary germ layers (during week 3)
  • endoderm, ectoderm, mesoderm
45
Q

What happens to inner cell mass before becoming three-layered?

A
  • it subdivides into 2 layers
  • upper epiblast and lower hypoblast
  • subdivided inner cell mass is embryonic disc
46
Q

What is the embryonic disc?

A
  • subdivided inner cell mass before becoming three-layered
  • with upper epiblast and lower hypoblast
47
Q

What do the extraembryonic membranes include?

A
  • amnion, yolk sac, allantois, chorion
  • form during first 2 to 3 weeks of development
48
Q

The amnion

A
  • develops when cells of epiblast fashion themselves into a transparent membranous sac
49
Q

What does the amnion contain?

A
  • amnionic fluid
50
Q

What is the amnion’s function?

A
  • buoyant environment: protects the developing embryo against physical trauma
  • helps maintain homeostatic temperature
  • prevents growing embryo parts from fusing together –> freedom of movement
51
Q

Where does amniotic fluid come from?

A
  • initially from maternal blood
  • after that, fetal urine
52
Q

What is yolk sac formed from?

A
  • cells of primitive gut which arrange themselves into a sac that hangs from the ventral surface of embryo
53
Q

How is yolk sac important for humans?

A
  • forms part of gut (digestive juice)
  • source of earliest blood cells and blood vessels
54
Q

Allantois

A
  • small outpocketing embryonic tissue at the caudal end of yolk sac
55
Q

Function of allantois

A
  • structural base for umbilical cord that links embryo to placenta
  • becomes a part of urinary bladder
56
Q

What does a fully formed umbilical cord contain?

A
  • embryonic connective tissue, umbilical arteries and veins
  • covered by amniotic membrane
57
Q

Organogenesis

A
  • formation of organs and organ systems
58
Q

Mean duration of pregnancy in weeks

A
  • 38 weeks
59
Q

Effect of pregnancy into female reproductive organs

A
  • become increasingly vascular and engorged with blood
  • increases vaginal sensitivity and sexual intensity
60
Q

Why do breasts enlarge and engorge with blood during pregnancy?

A
  • rising levels of estrogen and progesterone
61
Q

What does the hormone relaxin do?

A
  • produced by the placenta
  • causes pelvic ligaments and pubic symphysis to relax, widen and become more flexible
62
Q

How do multivitamins like folic acid help?

A
  • reduce the risk of having a baby with neurological problems
63
Q

Metabolic changes in the mother during pregnancy

A
  • placenta secretes human placental lactogen (hPL) also known as human chorionic somatomammotropin (hCS)
  • hPL works with estrogens and progesterones to prep breasts for lactation
  • promote fetus growth and exerts glucose-sparing effect on mother
  • maternal cells metabolize more fatty acids and less glucose
64
Q

Pregnancy effect on GI system

A
  • nausea and vomitting due to hCG, esterogen, progesterone
  • heartburn due to reflux of stomach acid into esophagus
  • constipation
65
Q

Pregnancy effect on urinary system

A
  • more urine produced
  • increased metabolic rate and uterus pressing against bladder
66
Q

Pregnancy effect on respiratory system

A
  • nasal mucosa become edematous and congested due to estrogens
67
Q

Pregnancy effect on cardiovascular system

A
  • total body water rises and BV increase as much as 40% by 32 weeks
  • safeguard blood loss
68
Q

Parturition

A
  • giving birth to the baby
69
Q

Rise in estrogen in the last weeks of pregnancy

A
  1. stimulate myometrial cells of uterus to form oxytocin receptors
  2. promote gap junction formation between uterine smooth muscle cells
  3. antagonizes progesterone;s quieting influence on uterine muscles
70
Q

What does oxytocin do?

A
  • causes placenta to release prostaglandins that stimulate more uterine smooth muscle gap junctions
  • more contractions
71
Q

Stages of labour

A
  • dilation, expulsion, placental stage
72
Q

What is the neonatal period?

A
  • four-week period immediately after birth
73
Q

Lactation

A
  • production of milk by mammary glands
74
Q

Hormonal control of lactation

A
  • rising levels of estrogen, progesterone, hPL stimulate hypothalamus to release prolactin-releasing factors
  • ant. pit. responds by secreting prolactin
75
Q

Advantages of breast milk

A
  • fats and ions r better absorbed and amino acids are better metabolized
  • beneficial chemicals like IgA protect infant from infections
76
Q

ulcer causing bacteria

A
  • helicobacter pylori

Entrance Biology (23 decks)

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