Lab 3: Semen Freezing, Thawing, and Handling for AI

Question 1

During dissection of the mature mouse, the two portions of the reproductive tract isolated were the ___ and ___. Why these?

Answer 1

Cauda epididymis and ductus deferens Because they are going to have mature sperm

Question 2

Which accessory sex gland was easily observed upon dissecting open the male mouse?

Answer 2

seminal vesicles

Question 3

What type of microscope did Dr. White use to isolate sperm from the two portions of the male reproductive tract in the petri dish?

Answer 3

dissecting microscope

Question 4

Which animal did Dr. White compare to the sperm being isolated from the two portions of the male reproductive tract within the petri dish?

Answer 4

snake

Question 5

Sperm are kept at ___ degrees Celsius immediately following isolation from the male reproductive tract. Why?

Answer 5

37 Keeping the samples warm and alive like they were still in the body

Question 6

Following isolation of sperm from the male reproductive tract, what is the purpose of pipetting the buffer solution a few times?

Answer 6

to properly mix the sperm homogeneously within the solution

Question 7

True or False: The sperm and buffer solution is centrifuged at a tigh speed for 30 seconds. Why is this so important?

Answer 7

True To pellet the sperm at the bottom

Question 8

True or False: Following centrifugation, sperm is located within the supernatant and not the pellet located at the bottom of the microcentrifuge tube.

Answer 8

Following centrifugation, sperm is not located within the supernatant, but the pellet located at the bottom of the microcentrifuge tube

Question 9

True or False: When loading semen straws, the purpose of creating air pockets is to allow for expansion during freezing so the straw doesn’t crack.

Answer 9

True

Question 10

Define vitrification

Answer 10

the process of freezing in the absence of ice

Question 11

Define cryopreservation

Answer 11

the process of cooling and storing cells, tissues, and organs at very low temperatures to maintain their viability

Question 12

The substance ___ is used for the cryopreservation and storage of frozen samples, and is ___ degrees celsius.

Answer 12

liquid nitrogen -196

Question 13

Explain the process of seeding and why it’s so important

Answer 13

supercool end of forceps place them on the strow - where sperm is place straw in liquid nitrogen tank for storage so we don’t get ice crystals that shoot through the semen and kill them a more consistent way of freezing

Question 14

Label the parts of a loaded semen straw as seen in the image below

Answer 14

A - freezing media

B - Freezing media and sperm

C - Air pockets

D - sealing powder