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B5 E) The Endocrine System
B5 E) The Endocrine System
There are two different messaging systems in the human body; the nervous system and the endocrine system (hormonal system). The first few sections of this whole topic was about the nervous system. The remaining sections will be about the endocrine system.
The endocrine system uses chemicals (hormones) to send messages around the body. The hormones are secreted by glands known as endocrine glands. The secreted hormones usually only affect certain cells in particular organs; the particular organ/ tissue that the hormone affects are known as the ‘target organ’. The endocrine glands secrete their hormones into the bloodstream. The hormones then travel around the bloodstream to the target organ.
The endocrine system uses chemicals (hormones) to send messages around the body. The hormones are secreted by glands known as endocrine glands. The secreted hormones usually only affect certain cells in particular organs; the particular organ/ tissue that the hormone affects are known as the ‘target organ’. The endocrine glands secrete their hormones into the bloodstream. The hormones then travel around the bloodstream to the target organ.
Differences Between the Nervous & Endocrine System
There are a few differences between the nervous system and the endocrine system (hormonal system).
The key differences between the nervous system and the endocrine system are shown in the table below:
There are a few differences between the nervous system and the endocrine system (hormonal system).
- The first difference is that the nervous system sends nerve impulses/ electrical impulses along a variety of different neurones. Whereas the endocrine system releases chemicals (hormones) into the bloodstream and these chemicals then reach their target organ.
- The nervous system is considerably faster than the endocrine system.
- The effect of hormones from the endocrine system tends to last for a longer period of time. Whereas the effect from the nervous system tends to be considerably shorter.
- The final difference is where the effects take place. In the nervous system, the effects are very localised because individual cells are targeted. Whereas, in the endocrine system, the hormones have an effect on a much larger area (such as an organ).
The key differences between the nervous system and the endocrine system are shown in the table below:
Different Glands
The human body contains many different endocrine glands. The majority of the endocrine glands are found in both males and females, but some are found in just females and others in just males. The diagram below shows the locations of the endocrine glands that we will look at in this course.
The human body contains many different endocrine glands. The majority of the endocrine glands are found in both males and females, but some are found in just females and others in just males. The diagram below shows the locations of the endocrine glands that we will look at in this course.
The Pituitary Gland
The pituitary gland is located at the base of the brain. The pituitary gland secretes many different hormones that causes lots of other glands in the body to also secrete hormones. The pituitary gland secretes follicle stimulating hormone (FSH), luteinising hormone (LH), thyroid stimulating hormone (TSH), growth hormones and many more. Sometimes the pituitary gland is referred to as the master gland as it secretes so many different hormones and causes other glands to secret hormones.
The Adrenal Glands
We have two adrenal glands in our body, which are located on top of both kidneys. The adrenal glands secrete adrenaline, which causes the body to prepare for either a “fight or flight” response.
The Thyroid Gland
The thyroid gland is found in the neck and it is responsible for regulating metabolic rate, heart rate and temperature. It secretes many hormones and the main one is thyroxine.
The Pancreas
The pancreas is responsible for regulating blood glucose concentration. It secretes insulin and glucagon.
Ovaries – Female Only
The ovaries are only found in females. The ovaries produce oestrogen and progesterone, which are used in the menstrual cycle.
Testes – Males
Testes are only found in males. The testes produce testosterone, which is responsible for puberty and sperm production (male gametes).
Final Note
We will be looking at all of these hormones and the effects that they have in the coming sections.
The pituitary gland is located at the base of the brain. The pituitary gland secretes many different hormones that causes lots of other glands in the body to also secrete hormones. The pituitary gland secretes follicle stimulating hormone (FSH), luteinising hormone (LH), thyroid stimulating hormone (TSH), growth hormones and many more. Sometimes the pituitary gland is referred to as the master gland as it secretes so many different hormones and causes other glands to secret hormones.
The Adrenal Glands
We have two adrenal glands in our body, which are located on top of both kidneys. The adrenal glands secrete adrenaline, which causes the body to prepare for either a “fight or flight” response.
The Thyroid Gland
The thyroid gland is found in the neck and it is responsible for regulating metabolic rate, heart rate and temperature. It secretes many hormones and the main one is thyroxine.
The Pancreas
The pancreas is responsible for regulating blood glucose concentration. It secretes insulin and glucagon.
Ovaries – Female Only
The ovaries are only found in females. The ovaries produce oestrogen and progesterone, which are used in the menstrual cycle.
Testes – Males
Testes are only found in males. The testes produce testosterone, which is responsible for puberty and sperm production (male gametes).
Final Note
We will be looking at all of these hormones and the effects that they have in the coming sections.