5/31 Lecture E3

Question 1

what are gametes?

Answer 1

sex cells (one from each parent)

Question 2

what is a zygote?

Answer 2

a fertilized egg (contains genes from both parents)

Question 3

What chromosome is male?

Answer 3

the Y

Question 4

what is the male copulatory organ?

Answer 4

penis

Question 5

What is the female copulatory organ?

Answer 5

vagina

Question 6

What are the primary sex organs that produce gametes?

Answer 6

testes or ovaries

Question 7

What are the secondary sex organs?

Answer 7

organs other than gonads that are necessary for reproduction:

male: system of ducts, glands, penis
female: uterine tubes, uterus, and vagina

Question 8

Where are the external genitalia located?

Answer 8

in the perineum

Question 9

What are the secondary sex characteristics?

Answer 9

features that distinguish the sexes and influence mate attraction

Question 10

When do secondary sex characteristics develop?

Answer 10

at puberty

Question 11

how many pairs of chromosomes are contained in cells?

Answer 11

23

Question 12

How many pairs of autosomes are contained in cells?

Answer 12

22

Question 13

How many pairs of sex chromosomes are contained in cells?

Answer 13

1 (XY for males; XX for females)

Question 14

How is the sex of a child determined?

Answer 14

by the type of sperm that fertilizes the mother’s egg, whether X-carrying or Y-carrying

Question 15

When do gonads develop in a fetus?

Answer 15

at 5-6 weeks; as gonadal ridges

Question 16

how many sets of ducts are adjacent to each gonadal ridge?

Answer 16

2

Question 17

In males, which ducts develop and which ducts degenerate?

Answer 17

mesonephric (wolfian) develop

paramesonephric (Mullerian) degenerate

Question 18

In females, which ducts develop and which ducts degenerate?

Answer 18

paramesonephric (Mullerian) develop

mesonephric (wolfian) degenerate

Question 19

What is the SRY gene?

Answer 19

the Sex-determining Region of Y chromosome

Question 20

What does the SRY gene code for?

Answer 20

a protein, testes-determining factor (TDF) that initiates development of testes

Question 21

When do the testes begin to secrete testosterone?

Answer 21

8-9 weeks

Question 22

What else do the testes secrete during development (besides testosterone)?

Answer 22

mullerian-inhibiting factor/substance (MIS)

Question 23

What does the genital tubercle become?

Answer 23

either the glans of the penis, or the glans clitoris

Question 24

What does the pair of urogenital folds form?

Answer 24

either encloses the male urethra to help form the penis, or forms the labia minora

Question 25

What do the pair of labioscrotal folds form?

Answer 25

either the scrotum or labia majora

Question 26

By when are the male/female genitalia distinctly formed?

Answer 26

week 12

Question 27

Male and female organs that develop from the same embryonic structure are called ____?

Answer 27

homologous

Question 28

that is the glans penis homologous to?

Answer 28

the clitoris

Question 29

what is the scrotum homologous to?

Answer 29

the labia majora

Question 30

what is the penis homologous to?

Answer 30

the labia minora

Question 31

what is the gubernaculum?

Answer 31

embryonic connective tissue cord extending from goand to pelvic cavity floor

Question 32

What is the vaginal process?

Answer 32

fold of peritoneum that extends into the scrotum

Question 33

What is the inguinal canal?

Answer 33

the pathway of low resistance through the groin created by gubernaculum and vaginal process

Question 34

What is the most common site of hernia in males?

Answer 34

the inguinal canal

Question 35

When does descent of the testes begin?

Answer 35

as early as 6 weeks

Question 36

What is the path of the testes?

Answer 36

inguinal canal --> scrotum by way of the gubernaculum

Question 37

When do the testes pass through the inguinal canal?

Answer 37

the 7th month

Question 38

What muscle accompanies the testes?

Answer 38

extensions of the internal abdominal oblique muscle

Question 39

What is cryptorchidism?

Answer 39

undescended testes

Question 40

in how many male births does cryptochidism occur?

Answer 40

about 3%

Question 41

What happens if cryptochidism remains uncorrected?

Answer 41

sterility or testicular cancer

Question 42

Where do ovaries get lodged?

Answer 42

on the inferior brim of the lesser pelvis

Question 43

In females, what does the gubernaculum become?

Answer 43

a pair of ligaments that supports the ovary and the uterus

Question 44

What borders the external genitalia?

Answer 44

the pubic symphysis, ischial tuberosities, and the coccyx

Question 45

which testicle is typically lower

Answer 45

the left

Question 46

What divides the scrotum into right and left compartments?

Answer 46

the internal median septum

Question 47

What is the perineal raphe?

Answer 47

the medial seam on scrotum surface that marks the location of the median septum