Year 12 Applied Science Level 3 Unit 9 Learning Aim B
Unit 9: Human Regulation & Reproduction
B: Understand the homeostatic mechanisms used by the
human body
Introduction
I am a volunteer for a UK charity that raises awareness and provides patients with
comprehensive support and up-to-date information about disorders of homeostasis.
I have been assigned to research common homeostasis disorders and to make an
illustrated report that details the normal and abnormal functioning of the endocrine
system and the treatments available to address disorders.
What is Hormonal Homeostatic Regulation?
In order to understand hormonal homeostatic regulation, you will need to understand
some key terms:
Hormones tell different tissues and organs or tissues to increase or decrease the
number of hormones. Hormones can speed or slow down the body's heart rate,
growing rate and metabolism. They regulate things like body temperature and
blood-sugar levels to make sure the bodily functions are working properly.
Hormones often bind to receptors to trigger physiological responses.
Nerves send signals by using electrical impulses that quickly deliver messages to
and from the brain. Nerves have special cells known as neurons that pass by
electrical impulses, neurons use charged particles to create a small electrical
current. This small electrical current moves from one neuron to another quickly. This
current helps maintain homeostatic regulation as it keeps track of the body's systems
and when it gets signals that something is out of character in any systems it can
quickly send orders to fix them.
Endocrine systems are a message system including organs and glands, in an
organism that deal with the feedback loops of hormones that are released by internal
glands. The Endocrine system releases hormones into the system. These hormones
are important for regulation of physiological processes. The endocrine system
consists of the following organs and glands:
1
, Year 12 Applied Science Level 3 Unit 9 Learning Aim B
● Pituitary gland - this gland is in the base of the brain and it releases growth
hormones, thyroid-stimulating hormones , prolactin , antidiuretic hormones ,
adrenocorticotropic hormones. The pituitary controls several other glands
including the thyroid and adrenal and is regulated by the hypothalamus. The
hypothalamus is located in the centre of the brain, shown in green on the
image on the left hand side below. The image on the right hand side below
shows the different areas inside the hypothalamus in more detail.
2
, Year 12 Applied Science Level 3 Unit 9 Learning Aim B
ADH (Anti Diuretic Hormones)
ADH plays an important role in regulating the balance of water and maintaining
blood pressure by controlling the reabsorption of water in the kidneys. ADH acts on
the kidneys to increase water reabsorption, when blood osmolarity is too high. Beta
cells are responsible for producing and secreting the hormone insulin , insulin
regulates glucose levels by promoting storage and uptake of glucose by cells.
Feedback diagram of water balance
● Thyroid gland- located in the neck, it produces thyroxine and controls
regulation of metabolic and energy rate.
● Parathyroid gland - located behind the thyroid gland , it produces parathyroid
hormones , which controls the regulation of calcium levels. When blood
calcium levels decrease, the parathyroid glands detect this decrease and
respond by releasing Parathyroid Hormone (PTH) into the bloodstream. PTH
acts on target tissues, primarily the bones, kidneys, and intestines, to increase
blood calcium levels. For example, PTH triggers bone reabsorption at the
kidneys when there is excess calcium and osteoclast activity, which is the
release of calcium into the bloodstream by bone breakdown when there is
insufficient calcium in the body.
3
Unit 9: Human Regulation & Reproduction
B: Understand the homeostatic mechanisms used by the
human body
Introduction
I am a volunteer for a UK charity that raises awareness and provides patients with
comprehensive support and up-to-date information about disorders of homeostasis.
I have been assigned to research common homeostasis disorders and to make an
illustrated report that details the normal and abnormal functioning of the endocrine
system and the treatments available to address disorders.
What is Hormonal Homeostatic Regulation?
In order to understand hormonal homeostatic regulation, you will need to understand
some key terms:
Hormones tell different tissues and organs or tissues to increase or decrease the
number of hormones. Hormones can speed or slow down the body's heart rate,
growing rate and metabolism. They regulate things like body temperature and
blood-sugar levels to make sure the bodily functions are working properly.
Hormones often bind to receptors to trigger physiological responses.
Nerves send signals by using electrical impulses that quickly deliver messages to
and from the brain. Nerves have special cells known as neurons that pass by
electrical impulses, neurons use charged particles to create a small electrical
current. This small electrical current moves from one neuron to another quickly. This
current helps maintain homeostatic regulation as it keeps track of the body's systems
and when it gets signals that something is out of character in any systems it can
quickly send orders to fix them.
Endocrine systems are a message system including organs and glands, in an
organism that deal with the feedback loops of hormones that are released by internal
glands. The Endocrine system releases hormones into the system. These hormones
are important for regulation of physiological processes. The endocrine system
consists of the following organs and glands:
1
, Year 12 Applied Science Level 3 Unit 9 Learning Aim B
● Pituitary gland - this gland is in the base of the brain and it releases growth
hormones, thyroid-stimulating hormones , prolactin , antidiuretic hormones ,
adrenocorticotropic hormones. The pituitary controls several other glands
including the thyroid and adrenal and is regulated by the hypothalamus. The
hypothalamus is located in the centre of the brain, shown in green on the
image on the left hand side below. The image on the right hand side below
shows the different areas inside the hypothalamus in more detail.
2
, Year 12 Applied Science Level 3 Unit 9 Learning Aim B
ADH (Anti Diuretic Hormones)
ADH plays an important role in regulating the balance of water and maintaining
blood pressure by controlling the reabsorption of water in the kidneys. ADH acts on
the kidneys to increase water reabsorption, when blood osmolarity is too high. Beta
cells are responsible for producing and secreting the hormone insulin , insulin
regulates glucose levels by promoting storage and uptake of glucose by cells.
Feedback diagram of water balance
● Thyroid gland- located in the neck, it produces thyroxine and controls
regulation of metabolic and energy rate.
● Parathyroid gland - located behind the thyroid gland , it produces parathyroid
hormones , which controls the regulation of calcium levels. When blood
calcium levels decrease, the parathyroid glands detect this decrease and
respond by releasing Parathyroid Hormone (PTH) into the bloodstream. PTH
acts on target tissues, primarily the bones, kidneys, and intestines, to increase
blood calcium levels. For example, PTH triggers bone reabsorption at the
kidneys when there is excess calcium and osteoclast activity, which is the
release of calcium into the bloodstream by bone breakdown when there is
insufficient calcium in the body.
3
