SAAT Biology Section 5.5 Vocabulary (Human Biology) - تحصيلي

Vitamin A role in the human body

Vision and health of the skin and bones

Vitamin D role in the human body

Health in the bones and teeth

Vitamin E role in the human body

Strengthening of red blood cell membrane

Vitamin B₂ role in the human body (Riboflavin)

Metabolism

Folic acid role in the human body

Formation of red blood cells and formation of DNA and RNA

Thiamine role in the human body

Metabolism of carbohydrates

Niacin (B₃) role in the human body

Metabolism and maintaining the nervous system

Pyridoxine (B₆) role in the human body

Metabolism of amino acids

B₁₂ role in the human body

Formation of red blood cells

Vitamin C role in the human body

Formation of collagen

Mineral Ca role in the human body

Strengthening of teeth and bone, nerve connection, and contraction of muscle

Mineral P role in the human body

Strengthening of teeth and bone

Mineral Mg role in the human body

Synthesis of protein

Mineral Fe role in the human body

Synthesis of hemoglobin

Mineral Cu role in the human body

Synthesis of hemoglobin and collagen formation

Mineral Zn role in the human body

Healing of wounds

Mineral Cl role in the human body

Balance of water in the body

Mineral I role in the human body

Synthesis of thyroid hormone

Mineral Na role in the human body

Nerve conduction, balance of pH

Mineral K role in the human body

Nerve connection, contraction of muscles

Endocrine system composition

Glands and functions such as a communication system

Endocrine blands produce

Hormones (which are released into the bloodstream and distributed to the body cells)

How the exocrine gland secretes

Secretes hormones through ducts

Hormone

A substance that acts on certain target cells and tissues to produce a specific response

Steroid hormones

Cholestoral (fat-based) hormones

Examples of steroid hormones

Estrogen and testosterone (affect the human reproductive system)

How steroid hormones work

By causing the target cells to initiate protein synthesis

Solubility of steroid hormones

Soluble in lipids and therefore can diffuse through the plasma membrane of a target cell

Are steroid hormones allowed to enter the nucleus?

Yes

Amino acid hormones

Nonsteroid hormones

Examples of amino acid hormones

Insulin glucagone and growth hormones

Amino acid hormones cannot

Diffuse through the plasma membrane

Instead of diffusing through the plasma membrane, an amino acid hormone

Bind to receptors found on the plasma membrane of a target cell

Once an amino acid hormon binds to a receptor,

The receptor acitvates the enzyme found on the inside of the new membrane (initiates a biochemical pathway)

Negative feedback

It returns to a system to a set point once it deviates sufficiently from that set point (the system caries within a particular range afterwards)

Endocrine system includes

All glands that secrete hormones

Pituitary gland

Sometimes called the ‘master gland’ becaues it regulates so many body functions

A few pituitary hormones act on

Tissues instead of specific organs

Human growth hormone (GH)

Secreted by the pituitary gland; regulates the body’s physical growth by stimulating cell division in muscle and bone tissue

Thyroid gland

Found in the neck, below the thyroid cartilage (Adam’s apple)

What the thyroid gland secretes

Thyroxine, it causes the cells of the body to have a higher rate of metabolism

Calcitonin

Secreted by the thyroid gland; it’s a hormone that is partially responsible for the regulation of calcium by lowering blood calcium levels by signalling bones to increase calcium abdorption

Parathyroid gland

Located near the thyroid gland

What the parathyroid gland secretes

Parathyroid hormone, which increases blood calcium levels by stimulating the bones to release calcium

(causes the kidneys to reabsorb more calcium and the intestines to absorb calcium from food)

Pancreas

Plays a crutial role in the production of enzymes that digest carbohydrates, proteins, and fats (also secretes insulin and glucagon)

When the pancreas releases insulin

When the blood glucose levels are high; to accelerate the conversion of glucose to glycogen (stored in the liver)

When blood glucose levels are low,

Glucagon is released from the pancreas to bind to liver cells and signal them to convert glycogen to glucose and release glucose into the blood

Adrenal glands

Located above the kidneys

Cortex

Outer part of the adrenal glands

Medulla

Inner part of the adrenal glands

Aldosterone

Released by the cortex; primarily affects the kidneys and is important for reabsorbing sodium

Cortisol

Raises blood glucose levels and reduces inflammation

Epinephrine (adrenaline)

A hormone released by the medulla

Norepinphrine

A hormone released by the medulla that is associated with the flight-or-fight response

Oxytocin

A hormone released by the hypothalamus

Antidiuretic hormone (ADH)

A hormone released by the hypothalamus; functions in homeostasis by regulating water balance

What Antidiuretic hormone (ADH) affects

Portions of the kidneys (collecting tubules), which causes kidneys to reabsorb more water and decrease the amount of water in the urine

Antidiuretic hormone (ADH) production

Stimulated by nasuea and vomitting, both of which cause dehydration