Brainscape's Knowledge GenomeTM

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


See full index

Developmental Biology > New Material for Final > Flashcards

New Material for Final Flashcards

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

What are the 3 main signaling molecules in avian axis formation?

A
  1. Shh activates nodal and cerebus
  2. Nodal activates pitx2 > interacts with organ primordia > left side
  3. Cerebus -| BMP -| Nodal (Nodal becomes active)
  4. Lefty -| this whole interaction (becomes left side??)

See slide 6

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

What are the main players in mammal (mouse) axis formation?

A

Anterior: Devoid of Nodal. And BMP, Wnt, FGF are blocked
Posterior: Nodal, Wnt, BMP, FGF, RA are high

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

What are the main players in mammal (mouse) axis formation?

A

Mechanical stress at day 5.5 > embryonic growth becomes restricted and the embryo only grows in the proximal-distal direction

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

What determines the mammal (mouse) axis formation anterior-posterior?

A

Patterning from hox genes and somites

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

What determines the mammal axis of formation dorsal-ventral?

A

Inner cell mass > dorsal

Hypoblast cells > ventral

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

What determines the mammal axis of formation posterior-anterior?

A

Fluid flow: Right to left
Two cilia populations (yellow – Nodal (motile), green – Primary (nonmotile)
Yellow cilia rotate counterclockwise to create flow toward left
Nonmotile cilia on left bend, activating mechosensitive Ca receptors
Ca gradient ultimately leads to activation of “left genes” such as Pitx2, lefty, nodal

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

Axis formation mammal left and right?

A

Bulbus cottis divides backwards

Same with lungs

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

What happens week 1-11 (embryonic period)?

A

Wk 3 - fertilization

Wk 4 - implantation, 1st pregnancy test (3.5 wk)

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

What happens Wk 5-8 (organogenesis)?

A

Wk 5 - primitive streak, gastrulation, neurulation
Wk 6 - 1st heart beat, PGCs migrate
Wk 7 - optic cup & lens vesicle
Wk 8 - genital ridge appears, interventricular septum
Wk 9 - cell-free cell DNA testing
Wk 10 - hands/feet approach midline, chorionic villus sample (10-14wk)

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

What happens week 11-birth (fetal period)?

A 
Wk 12 - end of 1st trimester
Wk 16 - sex determination by Ultrasound, Amniocentesis possible 
Wk 22 - limit of viability 
Wk 28 - End of 2nd Trimetest
Wk 37 - term 
Wk 40 - due date
Wk 42 - post term (get this baby out!)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What did Aristotle say about sex determination?

A

… Claimed the sex of an individual was determined by the heat to the male partner during intercourse. The more heated the passion, the greater the chance of a male child….

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

What did Gaken say about sex determination?

A

“Just as mankind is the most perfect of all animals, so within mankind, the man is more perfect than the woman, and the reason for this perfection is his excess heat, for heat is Nature’s primary instrument…the woman is less perfect than the man in respect to the generative parts. For the parts were formed within her when she was still a fetus, but could not because of the defect in heat emerge and project outside.”

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

When do human PGCs migrate?

A

5th-6th week

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

What is Klinefelter syndrome?

A

Male multiple X
Some men do not have obvious symptoms
Others exhibit: sparse body hair, enlarged breasts, wide hips, the penis does not reach adult size, testicles remain small, voices may not be as deep, cannot father children, have a normal sex life

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

What is Turner’s syndrom?

A

Missing/incomplete 2nd X
female X0
Characterized by short stature, lack of sexual development at puberty
May include a short neck with a webbed appearance, heart defects, kidney abnormalities
Great variability in the degree to which girls are affected

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

How is sex determined in Mammals?

A

Genital ridge develops into bipotential gonad

a) XY chromosome > gonad forming testis (sertoli, leydig cells). degradation of Mullerian duct. Mesonephric/Wolffian duct forms of internal. differentiation external genitalia
b) XX chromosomes > gonad forming ovary (granulosa, theca cells). Mullerian ducts forming internal genitalia. external genitalia form. loss of mesonephric/Wolffian duct.

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

Differentiation of gonad (male)

A

16-20 wk

  • rete connects to epididymis (form from mesonephric tubules)
  • Mesonephric/Wolffian Duct > Vas Degerens, epididymis
  • Mesenchyme testis cells > Leydig

Puberty

  • chords hollow at puberty = seminiferous tubules
  • sertoli cells secrete anti-Mullerian hormone
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Differentiation of gonad (male)

A
  1. The testes appear on the urogenital ridge (second month)
  2. The coelomic cavity evaginates into the scrotal swelling where if forms the processus vaginalis (middle of the third month)
  3. Testes begin descent into the scrotum guided by the gubernaculum (7th month)
  4. The processus vaginalis obliterates spontaneosly (shortly after birth)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Differentiation of gonad (female)

A

Germ cells on outer surface
Primary sex chords degenerate

Wolffian duct = nephric duct = vans & epididymis

Mullerian = off geneital ridge = oviduct uterus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What is the SRY gene?

A

Trangenic female + SRY has same genitalia as normal male

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

What are the 2 phases of secondary sex determination?

A
  1. Organogenesis

2. Puberty

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

What is the formation of male external genitalia?

A

Urogenital sinus - closes but forms the prostate
Genital tubercle - form glans penis (tip)
Labioscrotal fold/genital swelling - scrotum

Urethra starts as plate but folds inward to form tube running length of penis

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

How does the external female genitalia form?

A

Urogenital sinus - closes slightly but forms vaginal and urethral orifices, labia minor

Genital tubercle - clitoris

Labioscrotal fold/genital swelling - forms labia major

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

What are the hormones involved in the development of the male phenotype?

A
  1. Anti-Mullerian hormone (form sertoli)
  2. Testosterone (fetal Leydig & causes Wolffian duct primordial epididymus, vans degerenes, seminal vesicle)
  3. DHT (urethra, prostate, penis, scrotum. DHT appears to be more potent hormone than testosterone and is most active in prenatal and early childhood)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

What is androgen insensitivity syndrome?

A
  • XY w/ SRY gene
  • have testes > testosternone
  • no testosterone receptor
  • respond to estrogen > female traits (external genitalia form, breast development)
  • make AMH > no Mullerian duct = no uterus & oviduct & upper vagina
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

What is persistent Mullerian duct syndrome?

A

Both mesonephric components (vans deferens, epididymis) and Mullerian components (oviduct uterus) develop

Have cervix, uterus, oviduct
Vans deferens and male external genitalia

Female organs normal position, male vary
A. Testis in ovary position
B. 1 testis in abdomen, 1 in scrotum
C. both testis in scrotum

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

What is pseudohermaphrodism?

A

1 gonad but different secondary characteristics

Androgen insensitivity syndrome

Congenital adrenal hyperplasia (overexpression of testosterone-like hormones)

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

What is true hemaphroditism?

A

2 gonad types

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

What are the truths about hermaphroditism?

A
  1. Typically Y translocated to X chromosome
  2. If cell Y on active X = Y transcribed = male gonadal tissue
  3. If cell gets Y on inactive X = not transcribed = female
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

How do breasts form?

A

Raised epithelia form = mammary ridges run large portion of body, most lost in humans

a. mammary buds - cells collect in the center of the ridge. prior to birth - bud cells proliferate rapidly = cords
b. chords open @ skin = forme nipples and start branching @ base. Arrest until puberty, develop in females

Males
sex differentiation doesn’t begin until about week 8, thus nipples already formed
Once sex diff. begins, buds disappear and fail to form cords, but nipples left

Male same as female early, but cord degenerates & no ducts form

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

Breast formation in 3 steps

A
  1. Normal development with the formation of bud that branches
  2. Female + testosterone - bud initially forms (middle) but later degenerates (similar to what is seen in males)
  3. Male with no testosterone - follows female path
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

What are the main causes of female infertility?

A
  1. Ovulation factors (25%)
  2. Tubal factors (22%)
  3. Cervical/Uterine factors
  4. Peritoneal factors / endometriosis (15%)
33
Q

What are the main causes of male infertility?

A
  1. Endocrine and systemic disorders (1-2%)
  2. Genetic disorders of spermatogenesis (10-20%)
  3. Sperm transport disorders (10-20%)
  4. Idiopathic (all of the sudden there is an issue and we don’t know what the cause is) (30-40%)
34
Q

How many pregnancies will come to be with assisted reproductive technology (ART)

A

1 in 3

35
Q

If you have a regular cycle, chances are good you’re ovulating

A

True

36
Q

What are 3 ways to detect ovulation?

A
  1. Chart basal body temp (progesterone release at ovulation cause 0.5-1 F rise in temp)
  2. Ovulation kits (look for LH surge that comes right before ovulation)
  3. Progesterone (blood test on day 19-23 of cycle, progesterone is highest 7 days postovulation, if there is no elevation the person is not ovulating)
37
Q

What are the 2 damage types that can cause a tubal issue with fertility?

A
  1. Proximal tubal blockage (near uterus)

2. Distal tubal blockage (far from the uterus)

38
Q

What are the 5 main causes for proximal tubal damage?

A
  1. Pelvic inflammatory disease
  2. STI (Ghonnerea, clamidia)
  3. Appendicitis /Bowel disease
  4. Thickening/inflammation of tubal wall mucus plugs
  5. Endometriosis
39
Q

What are the 2 main causes for distal tubal damage?

A
  1. Pelvic inflammation (secondary to infection or endometriosis)
  2. Develop hydrosalpinges (blockages causing sausage-shaped tube)
40
Q

What is a hysterosalpingogram (HSG)?

A

Special type of x-ray to determine is fertility is caused by tubal factor

Fluid is injected into cervix to see if it flows out other end (opaque dye under real-time fluoroscopy). If it all stays in uterus you’re good to go. if it spills out you’ve got a tubal problem

41
Q

How can a tubal factor be corrected/treated?

A
  1. Surgery

2. IVF may be best option if too damaged

42
Q

What are 3 ways to see if infertility is due to a cervical / uterine problem?

A
  1. HSG
  2. Hysteroscopy (insert a camera to look at uterus)
  3. Saline sonohysterogram (SGH) = ultrasound while saline is injected thru cervix; allow both uterine wall and cavity visualization simultaneously
43
Q

What are the types of problems that occur in cervical / uterine infertility?

A
  1. Morphological issues (scarring)
  2. Fibroids
  3. Polups
44
Q

How can you treat cervical / uterine infertility?

A
  1. Antibiotics (if there is an infection)
  2. Hornomes (if uterine wall isn’t thickening)
  3. IUI
45
Q

What are 4 common uterus problems that cause infertility?

A
  1. Uterine leiomyomata - common benign smooth muscle monoclonal tumors
  2. Uterine anomalies - mullerian abnormalities (common in reoccurring preq. loss), congenital
  3. Luteal phase defect - corpus luteum inadequate progesterone
  4. Endometriosis
46
Q

What is a unique aspect about cervical/uterine issues?

A

You can still get pregnant and after you have 1 kid your body figures it out and can have others unassisted

47
Q

What is advanced maternal age?

A

35

48
Q

What are 3 tests to investigate ovarian reserve?

A
  1. FSH/estradiol levels - done right around mensus looking for a rise in FSh/estradiol that remains for 2-4 days
  2. Anti-mulleriun hormone level - produced by smaller follicles, low levels means there’s not a lot left (lower ovarian reserve)
  3. Transvaginal ultrasound - antral follicle count
49
Q

What are 4 treatment options for people lacking an ovarian reserve due to advanced maternal age?

A
  1. Fertility drugs
  2. IUI
  3. IVF
  4. Egg donation
50
Q

What is endometriosis?

A

Endometrum ends up in other places than the uterus (commonly the ovaducts)
Found in 35% of infertile woman with no other diagnosis
common in women with infertility, pelvic pain, or painful intercourse
May affect function of ovaries, fallopian tubes or implantation

51
Q

What are 2 causes for abnormalities in peritoneum of organs?

A
  1. Scare tissue

2. Endometriosis

52
Q

Treatment of endometriosis / peritoneal depends on what 4 factors?

A
  1. Age
  2. Severity of symptoms
  3. Severity of diesease
  4. If person wants children
53
Q

What are 3 techniques to treat endometriosis?

A
  1. Hormone therapy
  2. Pain medicantions
  3. Surgical treatments

Use laparoscopy to detect

54
Q

What is a laparoscopy?

A

Use CO2 to inflate abdominal cavity so you can see better, insert camera, use probe to remove ovaries?

55
Q

What 5 things are being looked at in a semen analysis?

A
  1. volume
  2. sperm count (total, concentration)
  3. Motility
  4. Morphology
  5. Infection
56
Q

How is a semen sample collected?

A
  1. Masturbation or special condom
  2. Abstain 48hr prior
  3. 2-3 collections a month apart
57
Q

What are additional forms of male testing that is not a semen sample?

A
  1. FSH - want high levels
  2. Testosterone - overtime testosterone drops
  3. Check DNA - don’t want fragmented DNA or chromosome defects
  4. Sperm vital staining - labels live (blue) vs dead (red) sperm
  5. Infection or inflammation - culture semen and see if bacteria grow
  6. Sperm antibody
  7. Membrane integrity - hypo-osmotic swelling test - live sperm will swell in the tails
  8. Swimming pattern - computer-assisted semen analysis
58
Q

Talk to me about the history artificial insemination

A

First in animals by Spallanzani in dogs 1780
1700 first human in scotland
1884 first US (sperm from med student bc father was sterile)

Simple, least invasive

59
Q

What are 5 reasons for artificial insemination with TDI (therapeutic donor insemination)?

A
  1. Both partners are carriers of heritable disease
  2. Couples who are serodiscordant for STI
  3. Couples who fail to achieve fertilization iwth IVF or ICSI
  4. Women without a male partner
  5. Couples who are incompatible for red cell antigens
60
Q

What is gamete intrafallopian transfer (GIFT)?

A

Gametes placed in fallopian tubes
Requires normal tubes
Laparoscopic surgery
>1% of ARTs

Fertilization occurs in the fallopian tube rather than lab (often religious reasons behind usage)

No confirmation of fertilization is possible

Catheder > abdominal cavity > up ovaduct

61
Q

What is zygote intrafallopian transfer (ZIFT)?

A

Zygote created in lab but transferred to tube
Laparoscopic surgery

Inseminate outside, put in ovaduct
Don’t want embryo outside of mom

62
Q

What problems can intrauterine insemination (IUI) overcome?

A
  1. Irregular ovulation
  2. Cervix issues
  3. Low sperm count or motility
  4. Erection or ejaculation issues
  5. Fertility preservation
63
Q

Is IUI common?

A

It is very common

Often 1st wave of therapy

64
Q

What are some reasons to do IUI with donor insemination?

A
  1. Donor not female partner
  2. partner sperm not viable
  3. Avoid father genetic diseases
  4. Single women or lesbian couples
65
Q

What is a vital step in IUI in regards to sperm?

A

Must have artificial capacitation (sperm maturation)

66
Q

What stage does the embryo get implanted in IUI?

A

Egg + sperm > fertilization in dish > implant at blastocyst stage

67
Q

For IVF, ovarian stimulation is required, why?

A

Hormonally induce multiple follicles at once because you want more than one egg

use LH and then use ultrasound to ID maturing follicles

68
Q

How are eggs retrieved for IVF?

A

Transvaginal ultrasound aspiration
Treat with hormones for several months
Insert catheter into vagina then probe goes through vaginal wall to grab eggs form ovary

69
Q

Fertilization for IVF

A

Eggs examined for maturity
Placed in IVF culture medium
Transferred to incubator waiting for sperm

Sperm obtained by masturbation or special condom
Alternative collection from testicle, epididymis, vas deferens (When semen devoid of sperm or blocked or low production)

Fertilization = Sperm placed with eggs overnight

70
Q

What is intracytoplasmic sperm injection (ICSI)?

A

Take a needle with sperm inside and inject it into an egg

If standard IVF was unsuccessful or if concerns are on the male side (sperm motility, acrosome, penetration)

60% of IVF in the USA

71
Q

Talk me through embryo culture

A

Day 1 post-IVF: 2 pronuclei
Day 2 post-IVF: 2-4 cell stage
Day 3 post-IVF: 6-10 cell stage
Day 5 post-IVF: blastocyst forms

72
Q

How did we end with a more boys from IVF?

A

Just so happens that male embryos divide ever so slightly faster - so they reach the 8 cell stage first and so they look like more promising embryos

73
Q

What is assisted hatching (AH)?

A

Female reproductive tract normally thins zona pellucida with enzymes

So, a hole is made in zona pellucida prior to transfer (either with acid (tyrode’s soln) or laser)

No evidence showing improved live birth rates

Slightly higher change of identical twins

Used for older women or couples with failed prior IVFs

74
Q

What can you do with the polar body when performing ICSI?

A

Can use the polar body to look at mom’s genetics (not identical DNA but gives good idea without disturbing the embryo)

75
Q

What is preimplantation genetic diagnosis (PGD)?

A

Punch hole in embryo and take out 1-2 trophoblast cells for genetic screening

More traumatic for the embryo - restricted to mom’s genetic material

76
Q

Talk me through embryo transfer

A

No anesthesia, maybe a mild sedative
ID cervix via speculum
1 or more embryos suspended in drop of culture medium in catheter - catheter thru cervix places fluid with embryo in uterus

Sometimes hormonally treat mom to help with implantation

77
Q

What are the 3 ‘levels’ comparing IUI, IVF, ICSI

A

IUI - first option - if problems with sperm delivery, motility, timing of ovulation

IVF - ovulation, sperm count/ morphology/ motility

ICSI - last option - problems with sperm egg binding

78
Q

How long do you have to be trying before considered infertile?

A

A couple less than 35 + trying for a year

A couple over 35 + trying for 6 months

79
Q

What are the 3 major regions of limb?

A
  1. Dorsal - knuckles and ventral-palm
  2. Anterior - thumb and posterior - pinky
  3. Proximal and distal

Developmental Biology (7 decks)

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