What type of reflex is ejaculation a part of
Parasympathetic Reflex
What happens to arterioles and the smooth muscle and why does that happen
Arterioles Dilate
Smooth muscles relax
Due to release of nitric oxide
The penis is now engorged with blood and the expansion compresses veins making blood leave slower
How is the reflex stimulated
Via sensory stimuli
Spinal reflex is initiated due to sympathetic discharge to the genital organs
Reproductive ducts will contract prismatically
What muscle induces contractions to propel semen?
Bulbocavernous Muscle
What does Viagra do ?
- This causes a prolonged arteriolar dilation hence a prolonged erection
What degrades cGMP
Phosphodiesterase 5
What makes up the seminal fluid ( 2 )
Seminal plasma and cells
What makes up the seminal plasma ( 3 )
Prostatic Fluid ( 30 % ) Epididymal Fluid ( 5 % ) Seminal Vesicle Fluid ( 65 % )
What cells are part of the seminal fluid
Spermatozoa
Leucocytes
Volume of Sperm during ejaculation
2 - 6 ml
pH of the sperm
7.2 - 8.0
What is used as a marker for seminal vesicle function
Fructose
What does prostaglandin help with in terms of sperm ?
Helps with sperm motility
What is used as a marker for epididymal function
Alpha - Glucosidase
- What produces it ?
- The epithelial cells of the prostate produces it
- What is the marker used for prostatic function
- Acid Phosphatase
What glycoprotein is incorporated into the sperm membrane
CD52
What are the prostatic secretions ( 6 )
How does the sperm cell membrane change during capacitation
Alterations in Surface Glycoprotein
Removal of cholesterol to increase fluidity of membrane
Loss of glycoprotein which exposes Egg Binding Protein
Fluctuation of Calcium ( to activate cAMP then phosphorylate protein )
How is the Egg Binding Protein Exposed
How does Capacitation affect the sperm
What increases uterine contractility to help in sperm transport ( 3 )
Journey of sperm
1) 2.5 x 10^8 will be deposited in the vagina
2) Only 100,000 will reach uterine cavity
3) < 50 reaches the distal end of the fallopian tube
4) Fertilisation occurs at the ampullary isthmic junction resulting in a delay ( Day 1 - 2 )
5) Another delay at the Utero - tubal junction ( D2 - D3 )
6) Egg enters uterine cavity as morula ( D3 - D4 )
7) Implantation of Blastocyst at Day 7