Lect 1

Question 0

What stages make up prenatal?

Answer 0

Day one - end of week 2 : pre embryonic
Week 3- end of week 8: embryonic
Week 9- birth ( week 38) : fetal

Question 1

What is embryology?

Answer 1

The study of prenatal development

Normal human structure/variation and prenatal care

Question 2

What is the main even in pre embryonic stage?

Answer 2

Implantation of the zygote into the uterine wall

Question 3

What are the main events in embryonic stages

Answer 3

The creation of germ layers and organogenesis

Question 4

What occurs during the fetal stage?

Answer 4

Growth and maturation of organ systems

Question 5

What’s the difference between gestational age and fertilisation age?

Answer 5

Gestational is obstetric, starts from 1st day of last normal menstral period, where as fertilisation would have occurred sometime prior to this event ( about 2 weeks -14 days)

Question 6

How long is the first trimester?

Answer 6

13 weeks

Question 7

When does almost 50% of spontaneous abortions happen?

Answer 7

The pre embryonic period ( day 1 - end of week 2)

Question 8

Most birth defects appear in what stage?

Answer 8

Embryonic period , when organogenesis is occurring

Question 9

Define conceptus

Answer 9

All structures that are derived from the fertilised egg( placenta, anything that is not normally in the mom before fertilisation

Question 10

What is induction?

Answer 10

Initiation of embryonic cell migration

Question 11

What is gametogenesis?

Answer 11

Gamete production and preparation for fertilisation - occurs through mitosis, meiosis, and maturation

Question 12

What state is the cell in before DNA replication occurs?

Answer 12

You have 1 diploid ( mom and dad) cell, 2n: 46 single chromatid chromosomes (23 mom: 23 dad) … This is normal

Question 13

What cell type do you have after DNA replication occurs during gametogenesis?

Answer 13

1 diploid cell -(mom and dad ) but doubled ..4n : 46 DOUBLE chromatid chromosomes

Question 14

After DNA replication Is the 1st mitosis decision. What does the cells look like ?

Answer 14

2 HAPLOID cells, (1 for maternal material and 1 with paternal material) but each has 2n: 23 double chromatid chromosomes

Question 15

What stage do you have 4 separate haploid cells (n:23 single chromatid chromosomes) ?

Answer 15

After the second mitosis decision

Question 16

When does OOgenesis begin ?

Answer 16

Prenatal ,is DNA replication portion of meiosis

Question 17

When does spermatogenesis begin?

Answer 17

Puberty is continuous. 86 day cycle

Question 18

When does meiosis one occur in famale OOgenesis?

Answer 18

Meiosis I occurs prenatal ( like DNA replication) and completes during ovulation

Question 19

When does meiosis II begin/ complete for females?

Answer 19

Meiosis II begins at ovulation and completes at fertilisation

Question 20

What are the products of meiosis for males and females?

Answer 20

Females make 1 oocyte ( and 3 polar bodies) males make 4 spermatids that mature into sperm around 86 days

Question 21

What are the three important factors of meiosis ?

Answer 21

1- forms diploid cell/ fertilisation 23 mom 23 dad single chromatid chromosomes
2- random assortment
3- variation and recombination

Question 22

If there is a chromosomal abnormality during meiosis what can happen ?

Answer 22

~ 25% spontaneous abortions and ~10% major birth defects

Question 23

What is it when chromosome pairs do not separate properly?

Answer 23

Nondisjunction - can cause monosomy or trisomy

Question 24

What is trisomy 21?

Answer 24

Down syndrome - extra chromosome at chromosome 21

Question 25

When you have one chromosome missing?

Answer 25

Turner syndrome . 45, X monosomy .. At 23 you have x but no Y

Question 26

What causes Klinefelter syndrome?

Answer 26

You have an extra chromosome: 47 xxy trisomy.

Question 27

When is the oocyte in MEIOTIC arrest?

Answer 27

After birth, before ovulation of the oocyte, correlation between increased wait in MEIOTIC arrest and increase risk to environmental influences.

Question 28

What is the male reproductive pathway?

Answer 28

TED EU: testis, epididymis, ductus deferens, ejaculatory duct, urethra

Question 29

What happened in the epididymis ?

Answer 29

Storage of sperm, sperm become motile, and released at ejaculation

Question 30

Where does OOgenesis ocur?

Answer 30

I the ovary

Question 31

What is capacitation?

Answer 31

7 hour conditions of sperm, removes glycoproteins coat on spermatids head

Question 32

Where does fertilisation typically occur?

Answer 32

Ampulla of uterine tube

Question 33

If more than one spam fertilises the egg it is called…

Answer 33

Polyspermy

Question 34

Before fertilisation what stage is the oocyte in?

Answer 34

The oocyte is arrested in meiosis II until fertilisation ( meiosis I was complete at ovulation)

Question 35

What is the “enzymatic drill”?

Answer 35

The acrosome reaction where the sperm drills through the zone polucida of the oocyte .

Question 36

What does the acrosome reaction trigger?

Answer 36

The zone reaction, where the ZP hardens to prevent polyspermy

Question 37

If polyspermy occurs, what can be the cause of this?

Answer 37

The zone reaction did not occur quick enough

Question 38

What is the result of the some membrane fusing with the oocyte?

Answer 38

Completing on meiosis II

Question 39

What are the fertilisation sequence of events?

Answer 39

1.) capacitation 2.) corona radiate penetration 3.) Acrosome and Zona reactions 4.) fusion and meiosis II completion 5.) zygote and sex is formed

Question 40

What is a pro nuclei ?

Answer 40

A haploid

Question 41

What percentage of couples are infertile?

Answer 41

15-30% reasons - insufficient sperm #, poor motility, PID, Ovulation disorders, endometriosis, cysts

Question 42

When is the greatest risk of spontaneous abortions ?

Answer 42

Pre embryonic period

Question 43

When is the greatest risk of birth defects?

Answer 43

Embryonic period ( week 3- end of 12)