Year 9 Science – Coordination Homework Name: ______
Background Information on Endocrine System
The word "endocrine" means to "secrete." And endocrine glands are internal secretions within your body. Endocrine glands pertain to glands that secrete directly into your bloodstream.
The endocrine glands include:
1. Pituitary gland - is inside the brain. It oversees the other glands and keeps hormone
levels in check, also known as the Master gland. It can bring about a change in hormone production somewhere else in the system by releasing its own ‘stimulating’ hormones. The pituitary gland is also connected to the nervous system via part of the brain called the hypothalamus.
2. Thyroid gland - is inside the throat. It produces thyroxine that controls the rate of metabolism.
3. Adrenal glands - are on top of each kidney. They make a number of different hormones,
such as adrenaline in times of stress.
4. Pancreas - an organ that produce digestive juice, which is inside the abdomen. It also makes insulin, which controls the amount of sugar in the bloodstream.
5. Ovaries - are inside the female pelvis. They make female sex hormones like oestrogen and progesterone.
6. Testes - they hang in the male scrotum. They make male sex hormones like testosterone.
An endocrine gland is a ductless gland that produces an internal secretion discharged into the blood, which is then circulated to all the other parts of the body. They are different from other ducted or exocrine glands such as salivary, oil, tear glands in which their secretions are discharged into ducts.
Hormones are the active principles of the endocrine glands and they produce effects on tissues sometimes near and sometimes far away from where they originated. The word hormone means "urging on" and that is exactly what hormones do. They urge on and actually cause things to start happening. They are the keys that unlock certain doors in the body.
Hormones that are secreted by the ductless glands may have a specific effect on an organ or tissue or a general effect on the entire body, as in the case of thyroid hormone, which affects the rate of metabolism.
The physiological processes that are affected by hormones are rate of metabolism and the metabolism of specific substances, growth and developmental processes, the secretory activity of other endocrine glands, the development and functioning of the reproductive organs, sexual characteristics, the development of personality and higher nervous functions, the ability of the body to meet conditions of stress and resistance to disease.
Common problems
Some common problems of the endocrine system include:
• Diabetes - too much sugar in the blood caused by problems with insulin production.
• Premenstrual tension - symptoms include bloating, breast tenderness and mood swings.
• Thyroid problems - when the gland is overactive (hyperthyroidism) or underactive (hypothyroidism).
Our body has over 30 incredible hormones busy regulating:
· Your body temperature
· When you are hungry or satiated
· When you sleep
· Your body weight
· How you break down and utilize food
· When you start puberty
· How you handle stress
· When you adrenaline kicks in during an emergency
· How much and when you will grow
JUST THE FACTS:
· Girls begin puberty between ages 9 - 13
· Boys begin puberty between ages 10 - 15
1. Label the diagram with the following glands:
testis, ovary, pituitary gland (at the base of the gland), thyroid gland (near the voice box), adrenal gland (at the top of kidney), pancreas (below the stomach)
2. Find out the two meaning of endocrine?
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3. Give two differences between endocrine and exocrine glands with an example of each type of glands.
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4. How are hormones transported around the body?
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5. Which gland produces insulin? Name the disease if they is a short of insulin in the body. What is the problem?
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6. Which gland produces hormones that change girls into women? Name these hormones.
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7. Why do scientists call the pituitary gland as the “Master Gland”?
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8. Which hormone will increase when you are under stress or during a fight?
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9. What is the function of Thyroid gland?
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