Staying in balance Flashcards
what is homeostasis?
keeping a constant internal environment
what does homeostasis involve?
balancing bodily inputs and outputs
what do automatic control systems do? an what does this make sure?
they keep the levels of temperature, water and carbon dioxide steady. This makes sure all cells can work at their optimum (best) level
what do receptors do?
to detect when things such as temperature change.
what do we need a processing centre for?
to receive this information and coordinate our response.
what do effectors do?
they produce a response that ensures our body temperature stays at 37°C.
what happens if our body gets too hot?
blood vessels in our skin vasodilate (become larger) and we lose heat and cool down.
what happens if our body gets too cold?
If we get too cold blood vessels in our skin vasoconstrict (become smaller), we lose less heat and our body warms up. Negative feedback makes sure this happens.
why is homeostasis important?
for our cells to function properly
Which of the following artificial systems is a model for how homeostasis works?
a camera
a lawn mower
an incubator
an incubator
Which of these statements about negative feedback is true?
Changes are ignored, causing a fall in the set level.
Changes are ignored, causing a rise in the set level.
Changes are reversed and returned back to the set level.
Changes are reversed and returned back to the set level.
what else does negative feedback control?
salt levels and oxygen in the blood
what does negative feedback make sure?
Changes are reversed and returned back to the set level.
what can a high temperature cause?
heat stroke and dehydration
what can a very low temperature cause?
hypothermia
what is blood temperature monitored by?
the hypothalamus gland in the brain
what is the body’s temperature?
37 degrees
what is the body temperature of 37 degrees linked to?
the optimum temperature for many enzymes
what happens when you have heat stroke?
skin becomes cold and clammy and pulse is rapid and weak
how does sweating help us?
it decreases our temperature so it matches with our environment
what does the evaporation of sweat require the body to do?
it requires body heat to change the liquid sweat into water vapour
what would happen if you had hypothermia?
slow pulse rate, violent shivering, can be fatal
what controls temperature extremes (over heat or under heat)?
nerves and hormonal system which trigger vasoconstriction and vasodilation
what controls blood sugar levels?
a hormone called insulin
why is hormone action slower than nervous reactions?
because the hormone travel in the blood
what is type one diabetes caused by?
the pancreas not producing any insulin.
what is type two diabetes caused by? and how can it be controlled?
either by the body producing too little insulin or the body not reaction to it.
what does insulin do?
insulin converts excess glucose in the blood into glycogen which is stored in the liver. This regulates the blood sugar levels
how is type 1 diabetes cured?
does of insulin
how is type 2 diabetes cured?
controlled by diet
at what temperature do cells work best?
37 degrees
if the body gets too hot or too cold what would stop working?
the enzymes in the body
name 3 activities that keep heat in your body
shivering, exercising and reduced sweating
name the stages that stop smells from sweat
taking a shower and wearing anti-perspirant stop bacteria from living on sweat and causing smell.
what is the level of glucose in the blood called?
your blood sugar level
what is glucose carried by in the body?
in the plasma
what happens when the level of glucose in the blood are too high?
insulin converts the excess glucose into glycogen, stored in the liver
what happens when the level of insulin is too low?
a lot of glucose is removed from her body by kidneys. This is exerted through urine
