Embryology

Question 1

chromosomal disorders/trisomies:
Edward syndrome
Down syndrome
Patau syndrome

Answer 1

trisomy 18
trisomy 21
trisomy 13

Question 2

week 1 of embryo development is called the ______ ______ and demonstrates the __ __ ___ phenomenon.

Answer 2

resistant period, all or none.

Question 3

weeks _ - _ are called the _______ _______, or ______ _______ _______ because all organ morphogenesis occurs at this time

Answer 3

3-8
embryonic period
maximum susceptibility period

Question 4

weeks _ - _ are called the _____ ______ or the _______ _______ _______ because all organ systems have already been formed. Injury here results in a functional derangement of an organ system

Answer 4

9-38

lowered susceptibility period

Question 5

TORCH infections

Answer 5

Toxoplasmosis
Other infx- coxsackie, syphilis, VZV, HIV
Rubella
Cytomegalovirus
HSV 2

mother is usu asx
neonatal infection more likely with primary maternal infection, congenital infection rate is 1%, 10% will be symptomatic, of which 25 % will have fatal disease

Question 6

Fetal Alcohol Syndrome

Answer 6

F: facial hypoplasia and forebrain malformation
A: Attention defecit disorder and Altered joints
S: Short stature, Septal defects and Small IQ

Question 7

testes development is determined by _____ Gene located on the _____ ____ __ ___ __ ________, which encodes for _____ __________ ______

Answer 7

Sry gene,
short arm of the Y chromosome
testes determining factor

Question 8

testosterone is secreted by the ________, and Mullerian inhibiting factor is secreted by the _______

Answer 8

Leydig, Sertoli cells

Question 9

describe the process of meiosis 1 with key events

Answer 9

prophase 1- synapsis and crossing over
metaphase 1- tetrads (paired homologous chromosomes) line up on metaphase plate
anaphase 1- homologous pairs separate
telophase and cytokinesis- separation of 46 homologous chromosomes without centromere splitting

Question 10

describe the process of meiosis 2 with key events

Answer 10

synapsis does not occur, crossing over does not occur

disjunction occurs with centromere splitting resulting in 4 haploid daughter cells

Question 11

sperm is produced inside the __________ __________, in the ______ cells, in the testes

Answer 11

seminiferous tubules, sertoli

Question 12

germ cell of the sperm is called the _____________

Answer 12

spermatogonia

Question 13

spermatogonia go through mitosis and differentiation to become ________ ___________

Answer 13

primary spermatocytes

Question 14

primary spermatocytes differentiate into secondary spermatocytes by ________ __, with each secondary spermatocyte containing __ chromosomes

Answer 14

meiosis I

23

Question 15

2 secondary spermatocytes differentiate into __ _______ each via ________ __

Answer 15

2 spermatids

meiosis II

Question 16

spermatids differentiate into _________

Answer 16

spermatozoa

Question 17

infertile males produce less than _________, and up to _____ of sperm are deformed

Answer 17

10 million sperm/mL of semen, 10%

Question 18

condition where the hypothalamus produces reduced levels of GnRF, leading to reduced levels of FSH and LG and reduced levels of testosterone.

Answer 18

Hypogonadotropic hypogonadism

Question 19

genetic disorder characterized by hypogonadoptropic hypogonadism and anosmia

Answer 19

Kallmann syndrome

Question 20

other diseases leading to male infertility

Answer 20

Klinefelter syndrome, cryptochordism, varicocele, hydrocele, mumps.

Question 21

all primary oocytes are formed by month __ of fetal life

Answer 21

5

Question 22

primary oocytes are arrested in ______ __ and present at birth

Answer 22

meiosis I

Question 23

at puberty, a primary oocyte completes ______ __ and forms a _______ ________

Answer 23

meiosis I, secondary oocyte

Question 24

secondary oocytes become arrested in metaphase of ______ ___ and are then ovulated, unless fertilization occurs, which then the secondary oocyte completes _______ ___ to form a mature oocyte

Answer 24

meiosis II, meiosis II

Question 25

______ __ does not occur until after fertilization

Answer 25

meiosis II