Slides in this set
CONTROLLING BODY PROCESSES
Nerve cells are neurons. The gap between neurons is a
synapse. Chemicals diffuse across the gap as that signals
can pass form one neurone to another.
Reflex actions are fast and automatic normally to protect
yourself from danger.
Receptor cells in the skin detect a stimulus such as a
change in temperature.
Sensory neurons carries information from a receptor.
Relay neurons in the spinal cord carries information a
sensory neuron to a motor neuron.
Motor neurons carries information to a effector.
Effector- in a muscle or a gland carries out a response such
as a muscle moving or a gland producing a hormone.…read more
Internal conditions in the body must be controlled, including
water and ion content, blood sugar level and temperature.
Water and ions leave the body from the skin and kidneys. Water
also leaves the body from the lungs.
Hormones are produced from glands. They are transported in
the blood stream to their target organs, where they cause a
change. Hormones control the menstrual cycle in woman.
FSH produced by the pituitary gland, causes an egg to mature
and stimulate oestrogen release.
Oestrogen produced by the ovaries, it stops the FSH production
and stimulates LH release and causes the womb to thicken.
LH produced by the pituitary gland, causes the release of an
egg at about day 14.…read more
Oral contraceptives contain hormones
(Oestrogen) that stop production of FSH.
Fertility drugs boost the levels of FSH. This helps
more eggs mature for use in in vitro fertilisation
or IVF.…read more
DIET AND HEALTH
People become too thin if they don't eat enough or they become
obese if they eat too much.
Lack of food can cause health problems including irregular
periods in women and reduced resistant to infections.
The metabolic rate is the speed of the chemical reactions in the
body. Exercise and inherited factors also influence it.
Heart disease, high blood pressure, arthritis and diabetic are
linked to excess weight.
Cholesterol is made by the liver from saturated fats.
Low density lipoproteins (LDLs) are bad cholesterol. They carry
cholesterol from the liver to the body cells.
High density lipoproteins (HDLS) are good cholesterol. They carry
cholesterol from the body cells to the liver.
Too much salt causes high blood pressure, leading to
cardiovascular disease.…read more
Drugs change chemical processes inside the body. Many
drugs are found naturally. New drugs are tested to make
sure they are effective and safe.
Thalidomide caused birth defects during the 1960's. Its
now used to treat leprosy but cannot be given to pregnant
Alcohol slows down reactions and leads to a loss of self
control. It can damage the liver and brain.
Nicotine is in tobacco smoke and has the effect of being
Carbon Monoxide is in tobacco smoke and has the effect of
reducing the ability of the blood to carry oxygen.
Tar is in tobacco smoke and causes cancer.…read more