EP Exam 2

Hypothalamus

Stimulates release of hormones from anterior pit.

& provides hormones for release from posterior pituitary gland

Anterior Pituitary gland

A gland that produces and secretes hormones such as growth hormone, prolactin, and adrenocorticotropic hormone, controlled by the hypothalamus.

ACTH

Controls release of cortisol from the adrenal cortex.

FSH

Sperm production and ovulation regulation in males and females.

LH

Controls testosterone and estrogen production, playing a key role in reproductive functions.

MSH

Stimulates melanin production in the skin and hair, influencing pigmentation.

TSH

Controls T3 and T4 hormones that regulate metabolism and energy levels in the body.

Growth Hormone

Bone growth and metabolism regulation, promoting growth and development in tissues.

Prolactin

Milk production and breast development during and after pregnancy.

Posterior Pituitary Gland

Releases hormones such as oxytocin and vasopressin, which are involved in water balance and uterine contractions.

Oxytocin

Secreted during labor and stimulates uterine contractions, also plays a role in social bonding and maternal behaviors.

ADH

Controls water volume and blood pressure by promoting water reabsorption in the kidneys.

Thyroid Gland

Produces hormones such as thyroxine (T4) and triiodothyronine (T3), which regulate metabolism, growth, and development.

T3/T4

A hormone produced by the thyroid gland that plays a critical role in regulating metabolism and energy production in the body.

Calcitonin

Involved in regulation of blood calcium levels and blocks release of of calcium from bones and stimulated excretion by kidneys.

Parathyroid Gland

Increases secretion rates of calcium from the bone and promotes absorption of calcium kidneys, helping to regulate calcium levels in the blood.

Adrenal Medulla

The inner part of the adrenal glands that produces catecholamines, including epinephrine and norepinephrine, which are vital for the body's fight-or-flight response.

Epinephrine/Norepinephrine

A hormone produced by the adrenal medulla that increases heart rate, muscle strength, blood pressure, and sugar metabolism, playing a crucial role in the body's fight-or-flight response.

Adrenal Cortex

The outer layer of the adrenal glands that produces steroid hormones such as cortisol, aldosterone, and androgens, crucial for metabolism, immune response, and blood pressure regulation.

Aldosterone

Maintains plasma sodium and potassium levels by regulating the reabsorption of sodium and the excretion of potassium in the kidneys, thus helping to control blood pressure and fluid balance.

Glucocorticoids

(Cortisol) regulates plasma glucose. They are steroid hormones produced by the adrenal cortex that influence metabolism, reduce inflammation, and help the body respond to stress.

Sex Steroids

(Androgens and estrogens) supports prepubescent growth.

Pancreas

An organ that produces insulin and glucagon, regulating blood sugar levels and aiding in digestion.

Insulin

Secreted via beta cells, promotes storage of glucose, amino acids, and fats from blood stream. It lowers blood sugar levels by facilitating cellular uptake of glucose and inhibiting glucose production in the liver.

Glucagon

Secreted via alpha cells, promotes mobilization of fatty acids and glucose. It increases blood sugar levels by stimulating glycogen breakdown in the liver and promoting gluconeogenesis.

Testosterone

A steroid hormone produced primarily in the testes, responsible for the development of male secondary sexual characteristics, muscle growth and development.

Estrogen

Regulates menstrual cycle.

Progesterone

Prepares uterus for reproduction and needed for pregnancy, labor and delivery.

Mechanisms involved in maintaining blood glucose concentration

1) Mobilization of glucose from liver glycogen stores, 2) Mobilization of free fatty acids from adipose tissue, 3) Use of amino acids, lactic acid, and glycerol via gluconeogenesis, 4) Blocking the entry of glucose into cells.

How glucose can be taken into the muscle at a high rate during exercise when plasma insulin is reduced

Even though insulin concentration decreases during exercise, glucose can be taken in at a high rate because

1) mobilization of glucose from liver and fatty acids from the adipose tissue,

2) increased plasma glucogen concentrations

3) lower insulin concentrations during exercise favors the mobilization of glucose from the liver,

4) glucose uptake is 7 - 20 times faster during exercise than at rest because the body is making ATP and using the glucose in the blood.

Changes occur with exercise of increasing intensity or duration

Epinephrine, Norepinephrine, cortisol, growth hormone, glucagon increase. Insulin decreases.

Factors that can influence blood concentration of a hormone

1) the rate of secretion of a hormone from a endocrine gland

2) the rate of a metabolism

3) the quality of transport protein

4) changes in plasma volume or composition.

Use of testosterone as aids to increase muscle size and strength

Increases muscle mass and muscular strength

Consequences of testosterone as aids to increase muscle size and strength

Reduced sperm count, breast development in men, acne, aggression, coronary heart disease, increased cholesterol, development of male characteristics in females.

Use of growth hormone as aids to increase muscle size and strength

Increases protein synthesis in muscle tissueand promotes fat utilization for energy.

Consequences of growth hormone as aids to increase muscle size and strength

Diabetes, hyperlipidemia, arthritis, carpal tunnel syndrome, muscle disease.

Endocrine system

Control and communication system that uses hormones secreted by endocrine glands directly into blood-stream to regulate various bodily functions, including metabolism, growth, and mood.

Hormone release

Gland release hormones into blood stream then circulates tissues to regulate metabolism, growth, and reproduction.

Hormone receptor interactions

Hormones affect only tissues that contain specific hormones receptor AKA lock and key model, where a hormone must bind to a specific receptor to have effect. A cell can have 500-100,000 receptors.

Factors influencing hormone concentration

Rate of a hormone secretion from gland rate of hormone metabolism or excretion (mainly by liver or kidney) quality of transport proteins in blood, changes in plasma volume.

Hormone types and action

Hormones are derived from amino acids, peptides, proteins, or steroids influencing how they interact with cells.

Steroid hormones

Can easily cross cell membranes and bind to intracellular receptors, leading to changes in gene expression/ alter protein synthesis.

Non-steroid hormones

(amino acids and proteins) are water-soluble and cannot easily cross cell membranes, typically binding to receptors on the cell surface to initiate a signaling cascade (signal transduction).

Homeostasis

Endocrine system works with nervous system to maintain homeostasis, balancing systems like blood glucose, blood pressure and heart rate (Neuroindocrinology)

Slow acting hormones

Thyroxine (T3/T4), cortisol, growth hormone

Fast acting hormone

Epinephrine, norepinephrine, insulin, glucagon

Stimulatory input

(Insulin increase) triggers the release of hormones to promote physiological responses.

Inhibitory input

(Insulin decrease) suppresses hormone release, reducing physiological responses.

Hypothalamus size

Almond

Bone growth

Stops growing in length between ages 18 and 25 when the growth plates close.

Dwarfism

Under secretion of growth hormone.

Giganticism

Over secretion of growth hormone, leading to excessive growth and height.

Acromegaly

Over secretion of growth hormone in adulthood.

Adrenal cortex secretes

Steroids hormones

Leptin

A hormone produced by adipose (fat) tissue that helps to regulate energy balance by inhibiting hunger.

Adiponectin

A hormone secreted by adipose tissue that enhances insulin sensitivity and regulates glucose levels. Helps weight loss.

Elderly hormone secretion

refers to the changes in hormone levels that occur with aging, impacting various physiological functions and metabolism.

Training effect

Epinephrine and Norepinephrine secretion rates decrease as body becomes more trained

Increased intensity

during exercise leads to greater hormonal responses and adaptations in the body.

During prolonged physical activity

Norepinephrine increases greatly while epinephrine slightly increases.

Calodulin

Protein needed to breakdown calcium

Hormone-substrates interaction

Depends on hormone sensitive lipase; as exercise intensity increases usage of fatty acids to make ATP decreases.

Factors that can cause body to use fewer triglycerides

1) higher levels of lactic acid

2) elevated hydrogen concentration inhibits hormone substrate levels

3) inadequate blood flow to adipose tissue

4) insufficient albumin

Albumin

Protein made my liver - transports hormones, neurotransmitter’s, and nutrients throughout the circulatory system

Absolute VO2

The total volume of oxygen consumed by an individual, regardless of body weight, often measured in liters per minute.

Relative VO2

The volume of oxygen consumed per kilogram of body weight, typically expressed in milliliters per minute per kilogram (ml/min/kg).

MET

A unit that estimates the energy expenditure of physical activities, where one MET is equivalent to the resting metabolic rate.

Calories burned

For every liter of oxygen consumed, will burn 5 calories

Gross VO2

Total volume of oxygen consumed during physical activity, without considering body weight. It is typically expressed in liters per minute.

Net VO2

The volume of oxygen consumed during physical activity, accounting for resting metabolic rate, typically expressed in liters per minute.