Everything Life Sciences Grade 10

(Marvins-Underground-K-12) #1

FACT


In 2007, a research
team from
University of
KwaZulu-Natal
found that plant
extracts from 16
plants used by local
healers as ’muti’
were highly
effective in treating
high blood pressure.


herbalists and diviners. Herbalists use plants to prescribe remedies to ailments. Diviners are
said to communicate with ancestral spirits in order to diagnose problems and ailments. In
Africa, traditional healers rely on up to 4000 plants for remedies. Pygneum, a traditional
medicine has been used in Africa and elsewhere to treat early forms of cancer for example.

Due to the high cost of modern Western health care systems and technologies, there has been
a recent focus on researching African traditional remedies and medicines. Traditional African
medicine may well have healing properties that have been recognised through generations
of use, and passed on in a cultural system. Because of the potential to reach greater masses
at lower cost there has been an attempt to combine traditional African medicine into the
continent’s health care systems. An example of this a 48-bed hospital that was opened in
Kwa-Mhlanga, South Africa, in 2010. The hospital treats patients using a combination of
traditional methods and Western healing methods.

Modern biotechnology DUMMY


In this section we will examine some aspects of biotechnology that have been applied in
modern medicine. Modern medicine is informed by medical research, and medical research
is based on the scientific method. Therefore these therapies are based on investigations that
have results that are reproducible. We will examine five achievements of modern medicine
and discuss the underlying ethical issues these new treatments and technologies present:


  1. Immunity and vaccines

  2. Antibiotics

  3. Blood transfusions

  4. Cloning

  5. Stem cell research

  6. Immunity and vaccines


Immunity is the body’s resistance to infection by bacteria and viruses. The body could be
infected by a host of microorganisms including bacteria, protozoa, viruses and fungi. The
body has a host of defences against infections. The body defends itself against infection
through a variety of means, such as physical, chemical and cellular barriers to infection.


  • Physical barriersinclude the skin, saliva, tears and mucus. They also include hairs in
    the lining of the respiratory tract known as cilia.

  • Chemical barriersinclude the various allergic responses that result in inflammation
    or swelling. These are caused by a chemical response system that results in the body
    releasing chemicals to attack any foreign objects entering the body. White blood cells
    known as eosinophils are normally responsible for the allergic response.

  • Cellular mechanismsexist to fight bacterial infections. These includeneutrophils,
    macrophages and which attack pathogens and ”engulf” and eat them through a pro-
    cess of phagocytosis.


The above defence mechanisms described are part of theinnateimmune system. The body
also has anadaptiveimmune system which ‘remembers’ each pathogen that invades the
body based on the specific markers on the pathogen. These markers are known as antigens.
When a foreign organism invades, the adaptive immune system launches an antigen-specific
response which destroys the infectious agent.

144 5.5. Applications of indigenous knowledge and biotechnology
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