Body, Cell Organisation and Homeostasis Flashcards
What is Homeostatic Imbalance?
A disturbance in homeostasis resulting in ill health
What is negative feedback?
It reduces the intensity of the original stimulus, bringing it back to normal. Eg: temperature
What is positive feedback?
It increases the original stimulus to push the variable further from the original stimulus. Eg: blood clotting and childbirth.
In what order do impulses travel through the body when a change in the environment is detected?
A change in stimulus is detected by a receptor and an impulse is sent along the afferent pathway to the central nervous system. Then an impulse is sent from the CNS along the efferent pathway to an effector which returns the variable to homeostasis.
What is homeostasis?
The maintenance of a stable internal environment.
How does homeostasis link to healthcare?
Homeostasis is disrupted by illness, unless treatment is administered then the homeostatic system will often fail.
Three ways the body cools down?
Sweating, arrector pili muscles relax, vasoconstriction.
Three ways the body heats up?
Shivering, arrector pili muscles contract so hairs stand up, vasodilation.
What organs are contained in the cranial cavity?
The brain and spinal cord.
What organ is contained in the spinal cavity?
The spinal cord runs down through the vertebral column.
What organs are contained in the thoracic cavity?
The heart and lungs.
What organs are contained in the abdominal cavity?
The stomach, liver, gall bladder, spleen, kidneys, pancreas and intestines.
What organs are contained in the pelvic cavity?
The bladder, urethra, bowel and in females: ovaries, uterus and vagina.
What separates the thoracic and abdominal cavity?
The diaphragm.
What are the two types of cell?
Eukaryotic (with a nucleus) and Prokaryotic (no nucleus).
