Sperm Transport

Question 1

Retrograde loss of sperm

Answer 1

The backward movement of sperm away from the female reproductive tract.

Question 2

Privileged pathways

Answer 2

Specialized routes within the female reproductive tract that facilitate sperm transport

Question 3

Capacitation

Answer 3

The process by which sperm become capable of fertilizing an egg

Question 4

Hyperactivation

Answer 4

-An increase in sperm motility characterized by vigorous, irregular movements
-Increased flagellar bend amplitude, Asymmetry, Lateral head displacement, and Velocity

Question 5

Rapid transport phase

Answer 5

-The initial phase of sperm movement through the female reproductive tract.
-Inviable sperm

Question 6

Sustained transport phase

Answer 6

-The slower, longer-lasting phase of sperm transport
-Trickle-like movement of sperm from reservoirs into the oviduct
-Viable sperm

Question 7

Sialomucin

Answer 7

-Low viscosity mucus that helps forward movement of sperm through privileged pathways
-A type of mucin that contains sialic acid and is found in mucus
-low viscosity

Question 8

Sulfomucin

Answer 8

-High viscosity mucus that traps sperm and is flushed out
-A type of mucin that contains sulfate groups
-High viscosity

Question 9

Know methods by which sperm and oocyte recognition occur.

Answer 9

-Chemotaxis: Chemo-attractants that may be present in follicular fluid in the egg. The ability of sperm to move toward and recognize specific chemical signals from the egg.
-Thermotaxis: 2 degree C difference between isthmus and ampulla. The ability of sperm to navigate based on temperature gradients.

Question 10

Be able to list and describe barriers to sperm transport.

Answer 10

-Vaginia
-Cervix
-Uterus
-Uterotubal junction
-Isthmus and sperm reservoir

Question 11

How does the Viginia, cervix, and uterus act as a barrier to sperm?

Answer 11

-Low vaginal pH
-Retrograde flow of semen
-Long uterine body and horns
-Leukocytic infiltration of sperm cells

Question 12

How does the Uterotubal junction act as a barrier to sperm?

Answer 12

-Folds in mucosa: Results in dead ends
-Viscous fluid
-Removal of seminal plasma
-Removal of defective, slow spermatozoa

Question 13

How does the Isthmus and sperm reservoir act as a barrier to sperm?

Answer 13

-Capacitation: Only capacitated sperm can fertilize
-Capacitated sperm die quickly unless they undergo acrosome reaction

Question 14

Be able to describe how the concentration, motility and morphology (normal vs abnormal) of sperm changes as it progresses through the female reproductive tract.

Answer 14

-Sperm concentration decreases as it progresses through the tract
-Percent of motile sperm increases
~50% at vagina
~99% at ampullary-isthmic junction
-Percent of normal sperm increases
~60% at vagina
~75% at ampullary-isthmic junction

Question 15

Be able to describe the transport of sperm through the cervix.

Answer 15

-Spermatozoa migrate along the walls and fold: Not through the lumen
-Cervical mucus
-“Privileged” pathways

Question 16

Cervical mucus

Answer 16

-Vehicle for sperm
-Filter for seminal plasma
~Sialomucin
~Sulfomucin

Question 17

“Privileged” pathways

Answer 17

-Specialized routes within the female reproductive tract that facilitate sperm transport
-Low viscosity environment in the valley of the cervix that creates a privileged pathway for healthy spermatozoa.
-Removal of non-motile sperm
-Removal of some abnormalities

Question 18

Know the 2 portions of the female reproductive tract where a great deal of the seminal plasma is removed.

Answer 18

Uterotubal junction
Uterus

Question 19

Describe the uterine immune response following insemination including why it’s good and why it’s a challenge to fertility.

Answer 19

-Immune response to sperm is slightly delayed after insemination
-Gives the sperm cells a start to get through the tract
-Remaining sperm are destroyed by immune cells

Question 20

How are sperm able to overcome the barriers made by the Viginia, cervix, and uterus?

Answer 20

-Alkaline pH of seminal plasma
-Cervical mucus moves sperm along
-Increased uterine contractions: Late follicular phase
-Immune response delayed

Question 21

How are sperm able to overcome the barriers made by the uterotubal junction?

Answer 21

Waves of contractions

Question 22

How are sperm able to overcome the barriers made by the Isthmus and sperm reservoir?

Answer 22

Hyperactivation

Question 23

Be able to describe the purpose and characteristics of the oviductal sperm reservoir.

Answer 23

-Sperm bind to oviductal epithelium in the uterotubal junction or isthmus
-Functions:
~Maintenance of spermatozoa between the onset of oestrus and ovulation
~Synchronization of Sperm & Egg Transport In Oviduct
~Prevention of polyspermy
~Capacitation
~Hyperactivation

Question 24

Be able to list the barriers to oocyte transport

Answer 24

-Follicle wall
-Infundibulum
-Ampulla

Question 25

How does the follicle wall act as a barrier to oocyte transport?

Answer 25

Weakening of wall

Question 26

How does the infundibulum act as a barrier to oocyte transport?

Answer 26

-Expanded cumulus -Fimbria -Mesosalpinx contractions

Question 27

How does the ampulla act as a barrier to oocyte transport?

Answer 27

-Oviductal muscle contractions -Cilia beat the oocyte to AIJ against flow of secretion

Question 28

Be able to describe how the oocyte is captured by the infundibulum and then transported down the oviduct.

Answer 28

-Expanded cumulus keeps the oocyte moving along -Fimbria -Mesosalpinx contractions -Oviductal muscle contractions -Cilia beat the oocyte to AIJ against flow of secretion -Infundibulum -> ampulla -> AIJ -> Isthmus -> UTJ

Question 29

Know how ovum transport is controlled.

Answer 29

-Estrogen enhances alpha adrenergic receptors, Stimulatory, and Isthmus contractions increase -Progesterone enhances beta adrenergic receptors, Inhibitory, and the Isthmus relaxes and allows embryo to go into the uterus

Question 30

Know what the “AI compromise” is and what happens if we inseminate earlier than that time or later than that time.

Answer 30

Earlier AI reduced fertilization rates and increased embryo quality

Question 31

Know how long it takes for sperm to be transported through the bovine tract to the oviduct.

Answer 31

4-16 hours

Question 32

Capacitation

Answer 32

-The process by which sperm become capable of fertilizing an egg -Strips the seminal plasma coating and some surface proteins so the parts needed to bind to the zona pellucida are exposed -These sperm die quickly without binding -NOT fully reversible

Question 33

Hyperactivation

Answer 33

-An increase in sperm motility characterized by vigorous, irregular movements -Increase sperm characteristics to move through cumulus cells -Increase Flagellar bend amplitude, Asymmetry, Lateral head displacement, and Velocity -Fully reversible