BIOLOGY (Endocrine)

• The endocrine system is composed of glands that secrete different types of hormones that affect almost every cell, organ, and function of our body
• Major endocrine glands in the human body:

  • Adrenal gland
  • Pancreas
  • Ovary
  • Testis
  • Pituitary gland
  • Parathyroid gland
  • Thyroid gland
• Hormones secreted by glands:

  • Adrenal gland: adrenaline
  • Pancreas: insulin
  • Parathyroid gland: parathormone
  • Testis: testosterone
  • Ovary: estrogen and progesterone
• Functions of progesterone and estrogen secreted by the ovaries:

  • Developing secondary female sex characteristics
  • Regulating the menstrual cycle
  • Thickening the lining of the uterus
• Endocrine system is not composed of nerves that transmit signals to different parts of the body
• Gland located at the base of the brain: Pituitary gland
• Gland that regulates blood sugar levels: Pancreas
• Gland responsible for flight or fight response: Adrenal gland
• Gland responsible for calcium regulation: Parathyroid glands
• The endocrine system is composed of different glands that secrete hormones regulating metabolism, growth, development, mood, and reproduction
• Hormones are organic substances released by the glands of the endocrine system directly into the bloodstream
• Hormones are capable of changing the physiological and metabolic behaviors of their target cells to maintain homeostasis
• Major endocrine glands in the body are the pituitary, thyroid, parathyroid, thymus, adrenal, pancreas, ovaries, and testes
• Pituitary gland:

  • Produces hormones that stimulate growth and control the functions of other glands
  • Hormones produced: Oxytocin, Growth Hormones (GH), Prolactin (PRL), Luteinizing Hormone (LH), Follicle Stimulating Hormone (FSH), Adrenocorticotrophic hormone (ACTH), Antidiuretic hormone (AH)
  • Located at the base of the brain
• Thyroid gland:

  • Produces hormones that regulate body metabolism and storage of calcium in bones
  • Hormone produced: Thyroid hormone
  • Located in front of the neck and below the voice box
• Parathyroid gland:

  • Produces hormones that control the calcium levels in the body and normalize bone growth
  • Hormone produced: Parathormone
  • Located in the neck
• Thymus gland:

  • Produces hormones that enable the body to produce T cells before puberty
  • Hormone produced: Thymosin
  • Located in front of the heart
• Adrenal gland:

  • Produces hormones that affect metabolism, immune system, blood pressure, and stress reaction
  • Hormones produced: Adrenaline and others
  • Located on top of the kidneys
• Pancreas:

  • Produces hormones that regulate blood sugar levels
  • Hormones produced: Insulin, Glucagon
  • Located behind the stomach
• Reproductive glands:

  • Testes (Males) and Ovaries (Females) produce hormones that control maturation of sperm, development of secondary sexual characteristics, influence development of secondary sexual characteristics in females, maturation of egg cells, and ovulation
  • Testosterone is produced by testes, while Estrogen and Progesterone are produced by ovaries
  • Testes are located in the scrotum, and ovaries are located in the pelvic area
• Pineal gland:

  • Produces a hormone that regulates the biological clock in some animals
  • Hormone produced: Melatonin
  • Located in the brain
• The pituitary gland secretes a hormone that enables the body to produce T cells
• The organ that makes estrogen and progesterone is the ovary
• The parathyroid gland produces hormones that control the calcium levels in the body
• The adrenal gland produces hormones that control the heart rate and breathing in times of emergency
• The hormones secreted by the pancreas are insulin and glucagon
• The pituitary gland is referred to as the body's 'master gland' because it controls the activity of most other hormone-secreting glands
• If a person's blood sugar level becomes unstable, the pancreas gland is involved
• The nervous system uses electrical impulses to send messages through neurons while the endocrine system uses hormones to send messages to the target cells through the bloodstream
• The purpose of the thyroid gland is to release thyroxin and calcitonin
• Osteoporosis is a disorder in which bones become fragile and breakable
• A rare condition that causes abnormal growth in children due to the decrease in the production and secretion of growth hormones is dwarfism
• The Endocrine System regulates, coordinates and controls:

  1. Growth and development.

  2. Male and female development.

  3. How your body uses energy.

  4. Levels of salts and sugars in your blood.

  5. The amount (volume) of fluid in your body. 6. Appetite.
• •The Endocrine Glands are the organs of the Endocrine System. It produce and secrete (release) Hormones. They are located all over your body.
• Hormones are chemical messengers that are secreted (released) from glands into the blood and affect cells in another part of the body.
• •Hormones only work on certain cells, called target cells.• The target cells have special receptors that "recognize" the hormones and allow them to influence that cell.
• What Controls the Hormones? External stimuli by way of nerves from the sensory organs in the nervous system Internal stimuli by way of nerves and other hormones from inside the body
• external means coming from outside of your body and internal coming from inside of your body.
• 1. Pituitary Gland ➤At the base of the brain. -Master Gland. -Stimulates growth, and controls the functions of other glands.
• Oxytocin. -Manages key aspects of the female and male reproductive systems (labor and delivery, lactation, and human behavior). -➤ Love Drug/ Love hormone