2.1 Flashcards
What are receptor cells
Groups of cells found in your sense organs
Examples of receptor cells that detect stimuli (5)
Light Sound Smell Taste Touch Heat
What causes a response?
- information detected by your body is sent along neurons (bundled together in nerves) to the brain
- brain processes the info received
- brain sends impulse to effectors (muscles/glands) causing a response
What is a reflex action
Automatic and rapid responses to stimuli
Reflect actions involve what 3 neurons?
Sensory
Relay
Motor
Sensory
Receptor cells —> CNS (brain/spinal chord)
Relay
Found in CNS
Sensory —> motor
Motor
CNS —> effectors
How longitudinal waves travel from vibrating objects so that we can hear sounds
(3)
- when a drum is struck,it vibrates causing air particles next to it to vibrate
- these vibrations pass energy into neighbouring particles
- this eventually causes your ear drum to vibrate so that we can hear sound
What is the human hearing range?
20-20,000 Hz
Significance or homeostasis
The body needs to maintain a constant, internal environment called a homeostasis
What are hormones?
Chemical substances that control many processes within the body
What are hormones secreted by?
Where are they transported to?
Glands
Transported to their target organs in the bloodstream
What do high blood glucose levels indicate?
Symptom of diabetes
How are type 2 diabetes controlled?
Lifestyle change
Diet/exercise
How are type 1 diabetes controlled?
Insulin change (Insulin dependent diabetes)
How levels are monitored/controlled by the pancreas:
Too high
Pancreas releases the hormone insulin into the blood causing the liver to remove Glucose from the blood and store it as insoluble glycogen
How levels are monitored/controlled by the pancreas:
Too low-
Pancreas releases glucagon causing the liver to convert glycogen back to glucose and release it into the blood
The body maintains a constant temperature using what?
Thermoregulatory centre in the brain
Constant temp
Increase/decrease sweating
Cools the body down by evaporation
Constant temp
Dilating blood vessels in skin capillaries
Increase blood flow to/heat loss from skin
Constant temp
Constricting blood vessels supplying skin capillaries
Decrease blood flow/amounts of heat lost
What happens through negative feedback?
Changes are reversed and returned back to normal
implications of loud sounds
tittinus
constant ringing in ear
what must a person do to stay healthy?
the body must keep itself at the right temperature
control sugar content in the bloodstream
the healthy body detects external changes using what?
sense organs and the process this information in the brain
nervous system coordinates response causing body to make physiological changes
what is involved in a relay
- receptor detects a stimulus
- sensory neurone sends signal to relay neurone
- motor–> effector
- effector produces response
info- neurons to brain
Receptors respond to a stimulus and send impulses along sensory—>CNS
•CNS coordinates info and sends impulses along motor—> effectors
•which bring about a response.
how does the body maintain constant temp, using centre in brain
- sweating
- constricting
- dilating
