Answer:
Sperm washing is the process in which individual sperms are separated from the semen. Washed sperm is used in artificial insemination using the intrauterine insemination (IUI) technique and in in vitro fertilization (IVF). It may also be used to decrease the risk of HIV transmission by an HIV-positive male, in which case the washed sperm is injected into a female using an artificial insemination technique.
Sperm washing involves removing any mucus and non-motile sperm in the semen to improve the chances of fertilization and to extract certain disease-carrying material in the semen. Sperm washing is a standard procedure in infertility treatment.
Explanation:
Sperm washing takes place in a laboratory following sperm donation.
Sperm may be washed by density gradient centrifugation or by a "direct swim-up" technique that does not involve centrifugation. In normal semen samples, centrifugation causes no more DNA damage to spermatozoa than a direct swim-up technique.[1]
Washed sperm is concentrated in Hams F10 media without L-glutamine, warmed to 37 °C (99 °F).[2] A chemical known as a cryoprotectant is added to the sperm to aid the freezing and thawing process.[3] Further chemicals may be added which separate the most active sperm in the sample, as well as extend or dilute the sample so that vials for a number of inseminations are produced.
Answer: The Source
Explanation:It's important to check the credibility of the online source.
Other important information to establish the credibility of an online source:
- Perspective
- Date
- Sources of the Website
- Title of the Publication
- Time of the Publication
D. A consumer buys or trades to receive a commodity available for sale or exchange
Which key nutrient has been known to reduce the risk for heart disease for all adults over the age of 51?
d. vitamin b12
Answer:
Opponent-process theory
Explanation:
The opponent- process theory is based on the idea that every time you are going to need a higher amount of something in order to get the same sensation since your body is going to have the tendendy to develop kind of a habit.
Let's say for example that you are scared of something like a snake, at the begining, it's going to be so hard to face the fear and dare to touch one, but after doing it the first time the fear is going to reduce little by little and at the end you will touch them feeling no discomfort or disgust.
In Helena's case the opponent-process is working the other way round, since every time in order to get the same cool sensation she will need a higher quantity of the thing that is making her have those nice sensations, in this case, cocaine.