The Endocrine System

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The Endocrine System
Hormones Hormones!!!
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• Even though the endocrine system doesnt
  seem very important to us, it really is! It
  affects almost everything in our bodies, and
  participates in moods, growth and development,
  sexual functions, reproductive processes, tissue
  function, and metabolism.

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These are the main parts of the endocrine system
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Hormones Glands

• The endocrine system is founded on hormones and
  glands.
• Hormones transfer info and orders from a set of
  cells to another. Each type of hormone is
  designed to affect only certain cells.

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• A gland is a bunch of cells that produce and
  gives off chemicals. A gland selects and removes
  materials from the blood, processes them, and
  secretes the finished chemical product for use
  somewhere in the body.
• For example, exocrine glands like the sweat
  glands release secretions in the skin or inside
  the mouth.

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Endocrine System Parts

• Hypothalamus
• Pituitary Gland
• Thyroid
• Parathyroids
• Adrenal Glands
• Pineal Body
• Reproductive Glands

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Hypothalamus

• In the lower central part of the brain
• The main link between the endocrine and the
  nervous systems.
• Nerve cells in the hypothalamus control the
  pituitary gland by producing chemicals that
  either stimulate or suppress hormone secretions
  from the pituitary.

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Pituitary Gland

• The gland is no bigger than a pea.
• Located at the base of the brain, and the most
  important part of the entire endocrine system.
• AKA The master gland because it makes hormones
  that control other endocrine glands.
• The production of hormones and secretions can be
  affected by emotions and seasons change.
• Divided into two parts.

The MASTER Gland
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The Division

• The tiny pituitary has two parts the anterior
  and the posterior lobe.
• The anterior regulates the thyroid, adrenals, and
  the reproductives activities. It makes hormones
  like growth hormones, prolactin (breastfeeding),
  thyrotropin, and corticotropin.
• The posterior releases antiduretic hormones,
  which balances the bodys water level. It also
  makes oxytocin, which activates the contractions
  of the uterus in a woman in labor.
• The pituitary also secretes endorphins, chemicals
  that act on the nervous sytem and reduce painful
  feelings. It also gets rid of hormones that
  signal the reproductive organs to make sex
  hormones. It also controls ovulation and the
  menstrual cycle.

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• The thyroid is in the front part of the lower
  neck, and is shaped like a butterfly.
• It produces the hormones known as thyroxine and
  triiodothyronine.
• These control the rate at which cells burn fuels
  from food to produce energy.
• Thyroid hormones are important because they
  participate in the growth and development of
  kids and teens bones and the nervous system.
• Attached to the thryoid are four small glands
  called the parathyroids, which, with the help of
  calcitonin, control the calcium level.

Thyroid
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Adrenal Glands

• There are two adrenal glands, one on top of each
  kidney.
• There are two parts, each of which makes hormones
  and has a different function.
• The outer part, or the Arenal Cortex, makes
  hormones (corticosteroids) that control the salt
  and water balance in the body, responses to
  stress, metabolism, the immune system, and sexual
  development/function.
• The inner part, or the Adrenal Medulla, makes
  hormones (catecholamines) that increases blood
  pressure and heart rate when there is stress.
  (ex. Epinephrine, or adrenaline)

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Pineal Gland

• The pineal gland, or the pineal body is in the
  middle of the brain. It secretes melatonin, a
  hormone that regulates when you sleep at night
  and wake up in the morning.

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Reproductive Glands!!!

• The gonads are the main source of sex hormones.
  Even though you may think that gonads are just in
  guys, youre wrong! Girls have them too

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Male Gonads

• In guys the male gonads, or testes are located in
  the scrotum. They secrete hormones called
  androgens, the most important of which is
  testosterone. These hormones tell a guy's body
  when it's time to make the changes associated
  with puberty, like penis and height growth,
  deepening voice, and growth in facial and pubic
  hair. Working with hormones from the pituitary
  gland, testosterone also tells a guy's body when
  it's time to produce sperm in the testes.

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Female Gonads

• The ovaries are located in her pelvis. They
  produce eggs and secrete the female hormones
  estrogen and progesterone. Estrogen is involved
  when a girl begins to go through puberty. During
  puberty, a girl will experience breast growth,
  will begin to accumulate body fat around the hips
  and thighs, and will have a growth spurt.
  Estrogen and progesterone are also involved in
  the regulation of a girl's menstrual cycle. These
  hormones also play a role in pregnancy.

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What Does the Endocrine System Do?

• Once a hormone is secreted, it travels from the
  endocrine gland that produced it through the
  bloodstream to the cells designed to receive its
  message. These cells are called target cells.
  Along the way to the target cells, special
  proteins bind to some of the hormones. These
  proteins act as carriers that control the amount
  of hormone that is available for the cells to
  use. The target cells have receptors that latch
  onto only specific hormones, and each hormone has
  its own receptor, so that each hormone will
  communicate only with specific target cells that
  have receptors for that hormone. When the hormone
  reaches its target cell, it locks onto the cell's
  specific receptors and these hormone-receptor
  combinations transmit chemical instructions to
  the inner workings of the cell.
• When hormone levels reach a certain normal
  amount, the endocrine system helps the body to
  keep that level of hormone in the blood. For
  example, if the thyroid gland has secreted the
  right amount of thyroid hormones into the blood,
  the pituitary gland senses the normal levels of
  thyroid hormone in the bloodstream. Then the
  pituitary gland adjusts its release of
  thyrotropin, the hormone that stimulates the
  thyroid gland to produce thyroid hormones.
• Another example of this process is parathyroid
  hormone. Parathyroid hormone increases the level
  of calcium in the blood. When the blood calcium
  level rises, the parathyroid glands sense the
  change and reduce their secretion of parathyroid
  hormone. This turnoff process is called a
  negative feedback system.

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What can go wrong

• Too much or too little of any hormone can be
  harmful to your body.

For example, if the pituitary gland produces too
much growth hormone, a teen may grow excessively
tall. If it produces too little, a teen may be
unusually short. Doctors can often treat the
problems by controlling the production of
hormones or replacing certain hormones with
medication. Some endocrine problems that affect
teens are
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Problems

• Adrenal insufficiency. This condition occurs when
  the adrenal glands don't produce enough
  corticosteroids. The symptoms of adrenal
  insufficiency may include weakness, fatigue,
  abdominal pain, nausea, dehydration, and skin
  changes.
• Growth hormone problems. Too much growth hormone
  in kids and teens who are still growing will make
  their bones and other body parts grow
  excessively. This rare condition (sometimes
  called gigantism) is usually caused by a
  pituitary tumor and can be treated by removing
  the tumor.

• Hyperthyroidism. Hyperthyroidism is a condition
  in which the levels of thyroid hormones in the
  blood are very high/low.
• Precocious puberty. If the pituitary glands
  release hormones that stimulate the gonads to
  produce sex hormones too early, some kids may
  begin to go through puberty at a very young age.

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The End

• Made for you by
• Chelsea Hunter
• Karina Emeric
• Shelby Kesic
• Roberto Ramos
• The Endocrine System

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Review Questions

• TRUE or FALSE?
• The endocrine system is founded on hormones and
  tissues.
• A gland is a bunch of cells that produce and
  gives off chemicals.
• The Pituitary gland is no bigger than a bean.

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Review Questions (cont.)

• What is a gland?
• a. Cells that produce and give off gland tissue.
• b. Cells that produce and give off chemicals.
• c. Transporters of blood to the heart.
• What two systems is the hypothalamus linked
  between?
• The nervous and the endocrine
• The respiratory and the endocrine
• The skeletal and the reproductive
• Which part of the endocrine is the most
  important, and nicknamed the Master Gland?
• The thyroid
• The testes
• The pituitary gland

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Review Questions (again)

• What gland is important because of the
  participation in development of kids bones and
  the nervous system its also shaped like a
  butterfly.
• Pineal Gland
• Ovary
• Thyroid
• The two parts of the adrenal gland are the
  Adrenal _______ and the Adrenal _______.
• What does the pineal gland regulate?
• Where are the male gonads located?
• In the penis
• In the testes
• In the scrotum
• The ovaries produce ______ and secrete the female
  hormones _________ and_____________.

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• List a few things that could go wrong with the
  endocrine system.