science Flashcards
endocrine system?
-not have ducts,
- secretory product hormones
Secretory products are released into the bloodstream, eventually reaching the target organ.
example- Thyroid glands,
exocrine system
-have ducts
-secretory products- Sweat, enzymes, mucus
Secretory products are released to an internal organ or the external surface through a duct.
examples, Salivary glands, liver
Hypothalamus
This gland is located in brain, controls your endocrine system. uses information from nervous system to determine when to tell other glands.
what hypothalamus controls
your mood, hunger and thirst, sleep patterns and sexual function
stimulus-response
-Mechanoreceptors
-photoreceptor.
-Thermoreceptor
-Chemoreceptor
Describe the importance of the following in homeostasis and the stimulus–response model.
a. Receptor
The receptor detects a change in a variable. If change is outside a set range, it communicates.
Effector
organs that respond to a change in a variable and initiate a response, in homeostasis this involves
a response to bring back within a normal set range.
Control centre
Once stimulus or change in variable is detected by a receptor, the control Centre receives this message and sends a message to an appropriate effector
Explain the difference between a positive and negative feedback system
Negative feedback occurs when a response is in the opposite direction of the stimulus, restoring the variable to its set range through a homeostatic mechanism. Positive feedback is an amplification of change in a
variable, moving it further from the set point.
Eating chocolate and releasing insulin
negative feedback
state the function of a sensory neuron
Sensory neurons are present in receptors and detect changes in the environment
what is the order of flow chart
stimulus-receptor-control centre-effectors-response
You open the curtains and notice the change in light
eyes and photoreceptors
On a spring afternoon, a cool breeze causes goosebumps to appear on your arms
skin and thermoreceptors
When someone leaves a gas tap on in the science labs, a smell fills the room.
nose and chemoreceptors
When you eat a large meal you feel full
stomach and mechanoreceptors
Strawberries have a lovely smell and they taste great too!
nose, tongue and chemoreceptors
The school bell signals that it’s time for lunch
ears and mechanoreceptors
Speed of message
nervous system
fast
endocrine system-
slow
speed of response
endocrine system-
usually slow
nervous system-
immediate
Duration of response
endorcrine-
longlasting
nervous-
short
spread of response
endocrine- usually slow
nervous- very localised
Spread of response
In circulatory system — in
Hormones (chemicals)
bloodstream
In nervous system — along nerves and across sypnase
Type of message
endocrine- hormones
nervous-electrical impulses
