0115 966 7955 Today's Opening Times 10:00 - 20:00 (BST)

Process of Reproduction in the Human Body: Comparing Genders

Published: Last Edited:

Disclaimer: This essay has been submitted by a student. This is not an example of the work written by our professional essay writers. You can view samples of our professional work here.

Any opinions, findings, conclusions or recommendations expressed in this material are those of the authors and do not necessarily reflect the views of UK Essays.

  • Sophie Jesuthasan

Explain the process of reproduction with particular reference to the role of the different structures within the male and the female reproductive systems. (212 words)

Within the female body, the ova develops within the ovarian follicles which are contained within the ovaries. The mature ova is ejected from the ovary and wafted by cilia along the oviducts. If not fertilised, the ova leaves the body through the menstrual cycle. If fertilised the now zygote implants itself in to the walls of the uterus, where it is begins to grow. Once the foetus is fully developed, the cervix dilates and is expelled from the vagina via the uterus. The breasts contain mammary glands; the alveoli develop during pregnancy, and the milk ducts increase in size and number. After delivery, prolactin signals the body to make milk.

Within the male body, the testes produce gametes. The gametes are carried through the vas deferens, which are smooth lined tubes that carry sperm to seminal vesicles, where they are mixed with seminal fluid then to the prostate gland where milky fluid, containing nutrients, is added. Bulbourethral glands line the urethra, to act as a lubricant and to balance the pH.

The sperm pass through the cervix and enter the uterus, where they move in to the fallopian tubes. Once a single sperm enters the ovum, the cells divide and move back down the fallopian tubes and implant on the uterus walls.

TAQ 2.

Using a table similar to the one below, explain how hormones control the reproductive system and how the levels of each hormone chance during pregnancy. (250 words)

Source of Hormone

Hormone

Function(s)

Interstitial cells

Testosterone

Stimulates sex drive and maintains spermatogenesis

Ovaries- non pregnant women

Placenta for pregnant women

Oestrogen

Promotes maturation and release of ovum for menstrual cycle

Levels increase in pregnancy and decrease quickly after.

As age increases, levels decrease, partially causing menopause.

Corpus luteum

Progesterone

Prepares endometrium for implantation of fertilised ovum. Suppresses oestrogen production in pregnant women.

Levels increase in pregnancy and decrease quickly after. As age increases, levels decrease, partially causing menopause.

Anterior pituitary gland

Luteinising hormone (LH)

Causes the synthesis and secretion of testosterone and androgen in men.

In women it stimulates ovaries to produce oestrogen and progesterone, triggers ovulation and promotes development of the corpus luteum. Production is prevented during pregnancy.

Anterior pituitary gland

Follicle stimulating hormone (FSH)

Stimulates the production of androgen-binding protein and the formation of the blood-testis barrier in men

Simulates and controls ovum production and maturing in females. Production is prevented during pregnancy.

Placenta

hCG

Levels double every 72 hours within the first 8-11 weeks after implantation, then will decline and plateau for the remainder of the pregnancy.

In pregnant women, signals the corpus luteum to supply progesterone to maintain endometrium.

Posterior pituitary gland

Oxytocin

In men it promotes the movement of sperm and the production of testosterone.

In women it stimulates labour and promotes the movement of milk in to the breasts

Hypothalamus

Gonadtropin-releasing hormone (GnRH)

Maintains of follicular growth, ovulation and corpus luteum in women and spermatogenesis in men.

Production is suppressed by high levels of oestrogen in pregnancy

(Boundless, n.d.)

TAQ 3

Using a table similar to the one below, critically evaluate the different forms of contraception using both the advantages and disadvantages of each before reaching a conclusion as to which are seen as the best methods (433 words)

Method of contraception

Evaluation of Advantages

Evaluation of disadvantages

Final evaluation

Condom

+ Good protection against STDs (CDC, 2014) +Only needed when having sex +Easily accessible +Most people can use +98% effective when used properly

- Can split or tear - 82%-98% effective if not used properly (CDC, 2015) -Latex allergies - Expensive -People may not take the time to put it on

If used properly they are highly effective as a way of preventing not only pregnancy but also STDs, which none of the other methods are able to do.

Pill

+More than 91% effective (Emed Expert and CDC, 2015) +Lightens menstrual cycles + Reduces risks of ovarian cysts +protects against PID +doesn’t affect future fertility + Easy to use

- Can take 2-3 months longer to get pregnant - Potentially severe side effects - Doesn’t protect against STDs -Must be taken at the same time every day - stops working if have diarrhoea or vomiting - expensive

Relatively effective for stopping pregnancy but provides no protection against STDs. Pill must be taken at the same time everyday and may not be as effective when unwell.

Coitus Interruptus

+Always accessible + No cost + No side effects + natural +no long term affects on pregnancy

- Requires self control - No protection against STDs - 4%-22% chance of pregnancy (ARPH) -limited information about sperm in pre-come

If properly carried out it is a relatively effective way not to get pregnant, and is completely free with no side effects. However, it provides no protection from STDs and a lot of self control.

Intrauterine Device

+ more than 99% effective (University of Michigan and CDC, 2015) + Cost effective + easy to use + safe to use whilst breast feeding + easy to remove +Copper IUD can be used as emergency contraception

- can only be inserted or removed by a professional - doesn’t protect against STDs - Lead to PID - Side effects include- heavy periods, backache and headaches

One of the most effective forms of preventing pregnancy. However, it doesn’t protect from STDs and side effects can be severe.

Rhythm Method

+ cheap + always accessible + natural + no effects on long term fertility

- sperm can live in the body for up to 7 days - Menstrual cycles can vary -Must have regular cycle - Requires periods of absintance - No protection from STDs - 13% chance of pregnancy (Mayo Clnic) - 9%-25% chance of pregnancy (womens health) - Cycle must be tracked - Cycle must be monitored for 6 months to a year first

There is also quite a high risk of getting pregnant and it offers no protection from STDs. However, for those wanting to take a natural approach, it could be used in conjunction with the coitus Interruptus method.

(CDC, 2015, youngwomenshealth.org, n.d.)

TAQ 4

What causes each of the following genetic conditions?(312 words)

1) Huntington’s Disease

It is an autosomal dominant condition found on chromosome 4. The mutated gene is known as Huntingtin (HTT) which contains repeated CAG codons. When the repeat occurs over 36 times, it causes deterioration of certain neurones within the brain. The more repeats the faster the degeneration. Early symptoms tend to be a general lack of coordination and this eventually progresses until movements becomes difficult and mental abilities are impaired. If one parent is a carrier and the other is not, there is a 50% chance the offspring will develop the disease and a 75% chance if both parents are carriers.

(Study.com, n.d.)

2) Sickle Cell Anaemia

It is an autosomal recessive condition found on chromosome 11. There is a mutation of the HBB gene, both beta-globin subunits of haemoglobin are replaced with haemoglobin S. It causes the molecules to stick to each other and fibres to attach within the cell. This changes the red blood cell in to a sickle shape. These cells are inefficient at absorbing and transporting oxygen, meaning oxygen doesn’t get round the body efficiently. They also become rigid, making them stick within the capillaries. Two carrier parents will have a 25% chance of having a sufferer and a sufferer breeding with a non-carrier will produce a carrier.

(S-cool, n.d.)

3) Cystic Fibrosis

It is an autosomal recessive condition found on chromosome 11. It renders the sufferer unable to create the Cystic Fibrosis Transmembrane Conductance Regulator (CFTR) protein that regulates internal salt and water levels. The mucus within the lungs becomes viscous, sticking to airways. The pancreas loses its ability to break down and absorb food, leading to lack of energy and slow growth. If two carriers have children, there is a 25% chance the offspring will be a sufferer, a 50% chance they’ll be a carrier and a 25% chance they’ll be clear of the condition. If a sufferer breeds with a non-carrier, the offspring will be a carrier.

(Biologyguide.net, n.d.)

TAQ 5

Genetic counselling is an important consideration, particularly for couples at risk of a range of genetic based conditions and predispositions. What different kinds of genetic counselling are there and what are they used for? Write a short essay explaining the use of such counselling. (599 words)

Genetic counselling is a non-directive way to explain, in an easy to understand manner; the different types of genetic testing available, the prospects of the disease and possible treatments, its inheritance pattern and possible uncertainties. It is carried out by an appropriately trained healthcare professional. There are three primary types of genetic testing available; molecular, chromosomal and biochemical.

Molecular genetic tests use short sections of DNA, to identify significant changes be it large ones such as missing sections or small changes such as alterations from the norm. This type of testing can only look for specific mutations with a known outcome, such as cystic fibrosis and Huntington’s.

Chromosomal genetic tests look at the individual features of a person’s chromosomes to see if there are any discrepancies. This can be done by karyotyping which looks at the chromosome as a whole; it is useful when looking changes in the number of chromosomes, such as in Down’s syndrome. Or fluorescent in situ hybridisation analysis can be used to look at small pieces of chromosomes to see if there or any missing or extra parts.

Biochemical tests look at the formed proteins for abnormalities, often used for newborn screening. It can be used to diagnose metabolic conditions such as maple syrup urine disease.

These genetic tests are preformed in a number of different ways; they can confirm conditions, determine the chance of developing a condition or predict the likelihood of passing the condition to offspring.

Diagnostic testing is used to confirm or whether an individual has a suspected genetic condition. Whilst it can be carried out at any point during a person’s life, it does not test for all genetic conditions. However, it allows for plans to be made in terms of medication and lifestyle.

Predictive testing is a good way for individuals to find out if they are likely to develop genetic conditions that are within their family history. A blood sample is taken and specific mutations are looked for. It is particularly useful in regards to risk of developing cancer, and then allows you to take steps to reduce your chance e.g. somebody with a mutated BRCA gene may choose to undergo breast surgery.

Pharmacogenetic testing gives you information on how certain medications will be processed by an individual, so that the best medication for your condition is used, as people can react very differently.

Carrier testing is done by testing the saliva or blood of the couple to predict what chance any children will have of carrying or developing the condition. It is offered to couples who have a family history of genetic disorders and people in certain ethnic backgrounds.

Prenatal tests are carried out during pregnancy to look for any genetic abnormalities. Non-invasive tests looking for down syndrome are carried out on everybody in the UK and some other basic genetic tests. If anything is suspected the mother will be referred on for Amniocentesis. This is the process of inserting a needle in to the amniotic sac to collect amniotic fluid, in which the chromosomes can be tested for chromosomal and genetic abnormalities.

Pre-implantation genetic diagnosis uses, fertilised eggs that are collected from IVF, the embryos are grown until blastomeres can be collected, and these cells are tested for the specific genetic condition. The unaffected cells are then transferred to the womb to develop.

Once results have come back, post-test genetic counselling should take place. It will allow the health care worker to discuss the full implication of the results, referrals to be made to those who can provide more support and a strategy to be discussed.

(ghr, 2015, nhs, 2013, patient, 2013)

Bibliography

Anon. (2014).Hormonal Regulation of Male Reproductive System Source.Available: https://www.boundless.com/physiology/textbooks/boundless-anatomy-and-physiology-textbook/the-reproductive-system-27/physiology-of-the-male-reproductive-system-253/hormonal-regulation-of-male-reproduct. Last accessed 7th May 2015.

Anon. (2014).Overview of the Anatomy of the Female Reproductive System.Available: https://www.boundless.com/physiology/textbooks/boundless-anatomy-and-physiology-textbook/the-reproductive-system-27/the-female-reproductive-system-255/overview-of-the-anatomy-of-the-female-reproductiv. Last accessed 7th May 2015.

Anon. (n.d.).What Is Huntington's Disease? - Symptoms, Genetic Cause & Treatment.Available: what-is-huntingtons-disease-symptoms-genetic-cause-treatment.html. Last accessed 4th May 2015.

Anon. (n.d.).Evolution in Action.Available: http://www.s-cool.co.uk/a-level/biology/evolution/revise-it/evolution-in-action. Last accessed 4th May 2015.

Anon. (2015).Reproductive Health.Available: http://www.cdc.gov/reproductivehealth/unintendedpregnancy/contraception.htm#. Last accessed 7th May 2015.

Anon. (2014).Choosing a birth control method.Available: https://www.arhp.org/Publications-and-Resources/Quick-Reference-Guide-for-Clinicians/choosing/Coitus-Interuptus. Last accessed 7th May 2015.

Anon. (2014).Contraception: Pros and Cons of Different Contraceptive Methods.Available: http://youngwomenshealth.org/2009/01/28/pros-and-cons-contraceptive-methods/. Last accessed 7th May 2015.

Anon. (n.d.).Cystic Fibrosis.Available: http://www.biologyguide.net/unit1/3c_cystic_fibrosis.htm. Last accessed 4th May 2015.

Anon. (2015).What are the types of genetic tests?.Available: http://ghr.nlm.nih.gov/handbook/testing/uses. Last accessed 7th May 2015.

Anon. (2013).Predictive genetic tests for cancer risk genes .Available: http://www.nhs.uk/Conditions/predictive-genetic-tests-cancer/Pages/Introduction.aspx. Last accessed 7th May 2015.

Tidy, C. (2012).Genetic Counselling- A guide for GPs.Available: http://www.patient.co.uk/doctor/genetic-counselling-a-guide-for-gps. Last accessed 7th May 2015.

Hoad-Robson, R. (2013).Genetic Testing.Available: http://www.patient.co.uk/health/genetic-testing. Last accessed 7th May 2015.

1

 

To export a reference to this article please select a referencing stye below:

Reference Copied to Clipboard.
Reference Copied to Clipboard.
Reference Copied to Clipboard.
Reference Copied to Clipboard.
Reference Copied to Clipboard.
Reference Copied to Clipboard.
Reference Copied to Clipboard.

Request Removal

If you are the original writer of this essay and no longer wish to have the essay published on the UK Essays website then please click on the link below to request removal:


More from UK Essays

We can help with your essay
Find out more
Build Time: 0.0024 Seconds