Question

Briefly state the roles of the following components of homeostasis control system:

1. For homeostatic control of body temperature,

when it is HOT(stimulus),

which part/s of the body serve/s as the sensor/s?

which part/s of the body serve/s as the control center/s?

which part/s of the body serve/s as the effector/s?

describe the response & corresponding feedback loop.

what happens to effectors in the skin?

when it is COLD (stimulus),

which part/s of the body serve/s as the sensor/s?

which part/s of the body serve/s as the control center/s?

which part/s of the body serve/s as the effector/s?

describe the response & corresponding feedback loop.

what happens to effectors in the skin & muscles?

2. For homeostatic control of blood pressure:

when one is exercising,

which part/s of the body serve/s as the sensor/s?

which part/s of the body serve/s as the control center/s?

which part/s of the body serve/s as the effector/s?

describe the response & corresponding feedback loop.

what happens to effectors?

3. For homeostatic control of heart rate:

when one is exercising,

which part/s of the body serve/s as the sensor/s?

which part/s of the body serve/s as the control center/s?

which part/s of the body serve/s as the effector/s?

describe the response & corresponding feedback loop.

what happens to effectors?

4. For homeostatic control of blood sugar:

when one is exercising heavily,

which part/s of the body serve/s as the sensor & control center?

which part/s of the body serve/s as the effector/s?

describe the response & corresponding feedback loop.

Answer 1

1.
When body temperature exceeds thermal set poin(37 degree celsius) its become hot. Sensors like Nerve cells pass signals to the temperature regulatory centre in brain which produce effector response by secreting sweat through sweat glands and also by Vasodialation.
When body temperature Drop below normal (Cold) nerve signals passes to blood vessels to constrict and sweat glands to remain inactive.As a result Body heat is getting conserved and returns to the normal temperature.

2.
When you are exercising, your heart starts pumping faster to meet the increased demand for oxygen and nutrients by your musculoskeletal system. As a result, systolic blood pressure rises. It's normal for systolic blood pressure to rise to between 160 and 220 mm Hg during exercise.
The rising blood pressure act as stimulus itself and also there is increse in arterial blood pressure above normal level,which results in the stimulation of baroreceptors in carotid sinuses and aortic arch and inhibition of vasomotor center.Those impulse traveling to brain along afferent nerves from baroreceptor results in the stimulation of cardiac inhibitory centers and inhibition of cardio accelerator centers.Brain pasess sympathetic impulses to heart for declining Heart Rate .Vasodialation also increses as a result of decling of vasomotor impulses. leads to the decreasing of Cardiac Out put and peripheral resistance which return blood pressure to homeostatic range (decresed B.P).
3.
When heart rate imbalances, there is variable change and that is what act as Stimulus which detected by receptor (Blood pressure will increse).The Baroreceptor will be active there and information sent along afferent pathway to the control center of brain.As a results information sent along with efferent pathway to Heart which produce Effector response. Response of effector feeds back to influence magnitude of stimulus and returns variable to Homeostarsis. There by reducing the heart rate.
4.
When blood glucose levels rises, Beta cells of the pancrease release insulin in to the blood. Insulin has hypoglycemic action. It enhances glycolysis in liver and muscles by inducing certain factors (PFK-1,PK,Muscle HK II).Liver takes up glucose and stores it as glycogen and also by peripheral tissues.

When blood glucose level false, Alpha cells in pancrease release Glucagon which has hyperglycemic action.It enhances hepatic glycogenolysis, gluconeogenesis and inhibit glucogenesis .Liver breakdown glycogen and release glucose into the circulation. and glucagone also stimulate hydrolysis of TG in adipose tissues by activating hormone sensitive TG lipase. this results in release of large amounts of free fatty acid in plasma from adipose tissue.as result glucose level rises and blood glucose level getting Maintained.