topic 5(Homeostasis) Flashcards
(24 cards)
Homeostasis
The regulation of the conditions inside your body to maintain optimum conditions for function in response to internal and external changes
Examples of automatic control systems
central nervous systems and hormonal communication systems/
components of automatic control systems
effector , coordination centre and receptors
function of components of automatic control systems
effector- produces a response which counteracts the change from the stimuli
coordination centre- recieves and processes information
receptor- detects a stimulus
stimulus
a change either internally or externally in the body
central nervous system
brain and spinal chord.
connected to the body by sensory and motor neurons
sensory neurons
carry information as electrical impulses from the receptors to the CNS
Motor neurons
carry electrical impulses from the CNS to effectors
effectors
Muscles and glands that respond to nervous impulses
Synapses
connection between two neurons
nerve signal is transferred by chemicals which diffuse across the gap
reflexes
rapid, automatic, unconscious responses that can reduce the chances of being injured
reflex arc
- stimuli(Bee sting)
- receptors take notice and action
3.impulses travel along a sensory neurone - impulses then passed along a relay neurone, via synapse,to the nervous system
5.impulses travel along a motor neurone, via a synapse - effectors notified and contracts muscle
required practical
drop a ruler before and after drinking a coffee to show the effects of caffeine
hormones
Chemical molecules released into the blood
produced and secreted by various glands, called endocrine glands. These glands make up your endocrine system.
Tend to have long-lasting effects.
Examples of glands
Pituitary gland- many hormones that regulate body conditions
Thyroid- thyroxine , which is involved in rate of metabolism , heart rate and temperature.
Adrenal gland- adrenaline, used in the ‘fight or flight’ response
pancreas- produces insulin, which is used to regulate blood glucose levels
ovaries(female) -produces oestrogen, which is involved in the menstrual cycle
testicles(male)-produces testosterone, which controls puberty and sperm production
Glucose
eating carbohydrates puts glucose into the blood from the gut.
vigorous exercise removes much more glucose from the blood.
Excess can be stored as glycogen in the liver and muscles.
Monitored by the pancreas, which uses insulin and glucagon
Type 2 diabetes
where someone becomes resistant to their own insulin
Also can cause someone’s blood sugar level to rise and reach a dangerous level.
Being overweight can increase the chances of developing type two diabetes
controlled by eating a carbohydrate-controlled diet and getting regular exercise
Puberty
releases sex hormones that trigger off secondary sexual characteristics
examples include facial hair and breasts
Type 1 diabetes
condition that effects ability to control blood sugar level
where the pancreas produces little to no insulin, which mean sugar level could rise to a level where it could kill.
cured by injections which removes glucose once food is digested.
the amount depends on somebody’s diet and amount of exercise
Menstrual cycle female
- uterus lining breaks down for around 4 days
- uterus lining builds up again, from day 4-14, into a thick, spongy layer full of blood vessels, ready to receive a fertilized egg
- an egg is developed and is released, also known as ovulation.
- the wall is then maintained for around 14 days. if no fertilized egg has landed on the uterus wall by the end. the spongy lining starts to break down and the process starts again.
FSH(Follicle-stimulating hormone)
produced by the pituitary gland
causes a egg to mature in one of the ovaries, in a structure called a follicle
stimulates the ovaries to produce oestrogen
oestrogen
produced by the pituitary gland
stimulates the release of a egg
can be used to prevent the release of a egg.
Used as a contraception
progesterone
produced in the ovaries by the remains of the follicle after ovulation
Used as a contraception by creating a thick mucus.
forms of contraception
condoms
sterilization-cutting the fallopian tubes
