Exam 4- Human Biology

Hormones

Act on specific cells in the body (target cells) that have the appropriate hormone receptor

Steroid Hormones

Enter target cells and bind to intracellular receptors (lipids)

Nonsteroid Hormones

Proteins; Bind to receptors on the target cell’s surface; binding initiates series of events inside cell altering cell activity

Posterior Pituitary Gland and what hormones are secreted

Connected to hypothalamus by neuroendocrine cells; secretes Antidiuretic hormone (ADH) and Oxytocin

Antidiuretic Hormone (ADH)

Conserves water in kidneys and regulates water balance in body

Oxytocin

Causes uterine contractions during labor, and milk ejection through neuroendocrine reflex

Anterior Pituitary

Controlled by hypothalamus and releases and inhibiting hormones from hypothalamus; Releases 6 hormones (ACTH, TSH, FSH, LH, PRL, GH)

Adrenocorticotropic Hormone (ACTH)

Stimulates adrenal cortex to release glucocorticoids (cortisol)

Thyroid-stimulating hormone (TSH)

Acts on thyroid gland, promoting release of thyroid hormones

Follicle stimulating hormone (FSH) and Luteinizing hormone (LH); gonadotropins

Stimulates growth, development, and function of ovaries and testes, not produced until puberty.

Prolactin (PRL)

Stimulates development of mammary glands and milk production

Growth Hormone (GH)

Has widespread effects on body; major effects on bone, muscle; most of growth-promoting effects occur during childhood and adolescence

Gigantism

Hypersecretion of growth hormone in childhood

Acromegaly

Excessive growth hormone over a long period in adults

Pituitary dwarfism

Hyposecretion of growth hormone; treated by administration of GH throughout childhood

Adrenal Gland contains:

Adrenal Cortex and Adrenal Medulla

Adrenal Cortex

Outer layer of adrenal gland; Glucocorticoids (cortisol) and Mineralocorticoid (aldosterone)

Adrenal Medulla

Inner layer of adrenal gland; Epinephrine and Norepinephrine

Glucocorticoids functions:

Maintain blood glucose levels during prolonged fasting and suppresses inflammatory responses

Mineralocorticoids functions:

Regulate sodium, potassium, and water balance, salt and water

Epinephrine (adrenaline) and Norepinephrine (noradrenaline) functions

Enhances function of sympathetic nervous system (fight or flight response) and affect cellular metabolism, blood pressure, inspiration, and heart activity

Thyroid Gland is located…

Below larynx in neck

Parathyroid gland location…

embedded in back of thyroid

Both thyroid and parathyroid are involved in …

Calcium balance (adjust calcium)

Thyroid is involved in regulating what

Metabolism

Goiter

Hypertrophy of the thyroid

The pancreas secretes __1__ and __2__ hormones

1. Glucagon

2. Insulin

Primary Action of The Pancreas

Raise and lower blood sugar levels

Two endocrine cells within pancreas

Alpha and Beta cells

Alpha cells

Secrete glucagon; raises blood sugar; causes breakdown of glycogen to glucose in liver

Beta cells

Secrete insulin; lowers blood sugar; Promotes uptake of sugar; Promotes conversion of glucose into glycogen, proteins, and fat

Type 1 Diabetes

Pancreas not producing enough insulin; insulin-dependent diabetes; results from autoimmune destruction of beta cells of pancreatic islets

Type 2 Diabetes

Non-insulin dependent and causes by insulin cell resistance; cells failing to respond to insulin

Digestive System Functions

Intake of food, disassembly, nutrient absorption, and elimination of wastes

Gastrointestinal Tract (GI)

Hollow tube ~30ft long containing Lumen, mouth, pharynx, esophagus, stomach, small and large intestine, rectum, and anus

Digestive system Accessory Organs

Salivary glands, liver, gallbladder, and pancreas

Pharynx

Common passageway for air and food

Two types of digestive processes

1. Peristalsis: Propels food forward

2. Segmentation: mixes food

Hydrochloric Acid in digestion

Produces a pH of ~2; breaking down large bits of food

Chyme

Partially digested food

Basal metabolic rate (BMR)

The energy needed by the body to perform essential activities, EXCEPT physical activity

Anorexia Nervosa

Excessive dieting, possibly to the point of starvation and death

Bulimia Nervosa

Binge eating followed by purging (vomiting and/or laxative use

Urinary System (kidneys)

Excretes nitrogenous wastes, excess solutes, and water