Term 2

Reproduction in Plants

A Mind-Map for the Reproduction in Plants

 

 Cross-Section of a Flower

 

 Practicals

2P13

Some pictures in the Nature Trail around the School...

Pollination

How does the stigma recognise the Pollen.

The pollen grains are of a certain shape and size and they can send out chemical signals, as the pollen grains land on the stigma, if it is of the certain shape and size of the species, then fertilisation would occur.

There is a difference between cross pollination and self pollination, cross pollination refers to pollen transferred from one flower to another on different plants of the same species. While self-pollination means there are male and female parts in the flower where the pollen grains drop from the anther above the stigma to fertilise.

Human Reproduction

Male Reproductive System

Structures	Functions
Male sex glands Seminal vesicle Prostate gland Cowper's gland	Responsible for the secretion of seminal fluid that can act as a lubricant and nutritive medium for the sperm
Epididymis	Stores sperm temporarily
Penis	Used for copulation and releases the sperm in the cervix of the female
Sperm duct	Conduct sperm to the urethra, by peristalsis
Urethra	Carries sperm (during copulation) and urine (during urination)
Testis	Produces sperm and male sex hormones (testosterone)
Scrotum	Responsible for maintaining the temperature of the testes, which is slightly below the normal body temperature. This is important for the development and survival of the sperm.

Femal Reproductive System

Structures	Functions
Ovary	Produces eggs and the female sex hormones (oestrogen and progesterone)
Uterus	Plays a part in the development of the embryo and formation of the placenta
Oviduct	Provides the environment for fertilisation to take place and conducts the fertilised egg to the uterus
Cervix	Opening to the uterus for the passage of sperms. In addition, the baby emerges through it during birth
Vagina	Accommodates the penis during copulation. Acts as the birth canal for the baby during birth.

Animation of the Menstrual Cycle

This is a easier version of the menstruation.

from the 1-5 days, menstruation occurs where the uterus lining breaks down)

5-14 days, uterus lining thickens

around the day 14 about day 11 to 16, "fertile days", would be the release of an ovum, however it only survives for 24 hours

day 14-28, *endometrium thickens (*tissues rich in blood capillary)

• this cycle dates can vary, as everyone is different such as the stress levels
• this cycles continues forever till menopause

Sexually Transmitted Diseases

1. AIDS Information Caused by the HIV virus that invades the immune system, resulting in "well carriers" to severe and fatal disorders. Spread: Contact with infected blood, semen, vaginal fluids mainly by unprotected sex and needle sharing and maternal transfer. - unprotected anal sex - unprotected vaginal sex - unprotected oral sex - injection of tainted blood - injection by needle-sharing - sharing objects and infected fluids - maternal blood to fetus

HIV Stage (1* - 14 years) - Flu-like symptoms may occur early or late - Most look and feel well for years - Infectious carrier - Skin & lung infections common in later years - HIV = antibody test indicates infection - 25% of infants born to HIV mothers will be infected

Complications: - HIV progresses to AIDS Stage (2 - 5 years) - Immune system destroyed - AIDS defining illnesses fatal (pneumonia, cancer, dementia, wasting, cancer of the cervix) Treatment: - Yes - early treatment is best Cure - No

2. GENITAL HERPES (HSV) Caused by a Herpes Simplex Virus with ulcerating blisters occurring on the genitals or anal area. May be spread to the mouth. Spread: - unprotected vaginal sex - unprotected anal sex - unprotected oral sex - direct touch skin-to-skin

- Many people feel fatigued, and have a fever. - Painful blisters itch, redden the skin, form into groups and ulcerate. - Ulcers crust and may heal with scarring

Complications: - The virus hides in nerve endings and reoccurs Treatment: - Yes (Acyclovir - no cure) Cure - No

3. GONORRHEA Info Caused by bacteria that commonly infects the genitals, anus and throat. Spread: by infected semen and vaginal fluids - unprotected vaginal sex - unprotected anal sex - unprotected oral sex

- Most women show NO symptoms or some vaginal discharge, pain on urination, frequency Men usually notice thick yellow-green discharge from the penis, pain on urinating, pain in penis. Men and women if infected in the rectum have pain, bleeding and discharge. Sore throats if the throat is infected.

Complications: Women: - sterility; pelvic inflammatory disease Men: - sterility, swollen testes - urinary infections Men and women may have heart, brain and liver infections, arthritis Treatment: - Yes (antibiotics) Cure - Yes, although some strains are resistant

4. SYPHILIS Information Caused by the Treponema Pallidum bacterium which develop a staged disease over years. Highly contagious, but cannot survive outside the body. Affects the skin and any organ. Spread: By contact with infected blood, semen, vaginal fluids or pus. - mother to unborn - direct touch - close body contact - unprotected anal sex - unprotected vaginal sex - unprotected oral sex - kissing - injecting blood (needle sharing)

Early stages shows painless sores, swollen glands and skin rashes. Sores may be inside the vagina or anus and go unnoticed. Stage 2. Rashes, new sores, flu-like symptoms, swollen glands, brain infection

Complications: - Skin, bone, heart disease - Brain disease - Dementia - Blindness if left untreated Treatment: - Yes (antibiotics) Sex contacts must be examined Cure - Yes (with treatment)

Reference:
Vaughn's Summaries

Birth Control

• Temporary methods allow the couple to still have children, if they stop using the methods, they can be natural or artificial.
• Natural methods are abstinence, withdrawal method and rhythm method
• Artificial methods include using of condoms, spermicide, birth control pills, intra-uterine devices and diaphragms

Reflections

This topic is something very important, as it is also sexuality education for students, it teaches many knowledge that will or might be very important to our lives. For the plant reproduction, we learnt of many ways how the plant fertilise where the processes are quite similar to humans such as fertilisation and so on. The cross section of the flower is something that i liked most in the topic, due to it being specific on the details, and also gives us more understanding. Many problems such as Sexually Transmitted Diseases could be caused if people do not practice safe sex, in which I learnt a lot, from how to keep myself safe. After these topics, my science knowledge has definitely improved, and what I learned are something that can be applied for the future.