Test 1: Endocrine & Digestive System

What are the two major control systems of the body, and how do their speeds compare?

The nervous system (fast-acting) and the endocrine system (slow-acting).

Endocrine Glands

ductless and release hormones into the body to maintain homeostasis

Exocrine Glands

secrete non-hormonal substances through ducts onto surfaces. 

Do some organs have both endocrine and exocrine functions?

Yes, organs such as the pancreas and gonads (ovaries and testes) have both endocrine and exocrine functions

What are the two main chemical classes of hormones?

Amino acid–based hormones and steroid-based hormones

Where are receptors located for steroid-based vs. amino acid–based hormones?

Receptors for steroid-based hormones are located inside the cell; receptors for amino acid–based hormones are located on the cell membrane. 

Which class of hormones uses a second messenger system?

Amino acid–based hormones (which bind to cell membrane receptors). 

Which hormones are water soluble and which are lipid soluble?

Water-soluble: Amino acid–based hormones. Lipid-soluble: Steroid-based hormones and thyroid hormone. 

What are lipid-soluble steroid hormones derived from?

Steroid-based hormones are derived from cholesterol

Which hormone is amino acid–based but acts as lipid soluble?

Thyroid hormone.

What hormones are produced by the anterior pituitary (adenohypophysis)?

Growth Hormone (GH), Thyroid Stimulating Hormone (TSH), Adrenocorticotropic Hormone (ACTH), Follicle Stimulating Hormone (FSH), Luteinizing Hormone (LH), and Prolactin. 

Where are posterior pituitary hormones made, and what are they?

Made in the hypothalamus (stored/released by posterior pituitary): Oxytocin (OXT) and Antidiuretic Hormone (ADH). 

What are the two thyroid hormones and what do they do?

Thyroid Hormone (T_3/T_4): Controls metabolism. Calcitonin: Lowers blood calcium. 

What does Parathyroid Hormone (PTH) do?

Raises blood calcium levels. 

What three steroid hormones come from the adrenal cortex?

Aldosterone, Cortisol, and Androgens

What does the adrenal medulla release, and is it essential for life?

Epinephrine and Norepinephrine; no, it is not essential for life. 

What do pancreatic alpha and beta cells release?

Alpha cells: Glucagon (raises blood sugar). Beta cells: Insulin (lowers blood sugar). 

What hormones do the ovaries and testes make?

Ovaries: Estrogen and Progesterone.

Testes: Testosterone.

What causes Diabetes Insipidus vs. Diabetes Mellitus?

Insipidus: ADH problem. Mellitus: Insulin problem. 

What is the main difference between Type 1 and Type 2 diabetes?

Type 1: No insulin made. Type 2: Cells resist insulin.

What hormones do the heart and kidneys produce?

Heart: ANP (lowers blood pressure). Kidneys: Erythropoietin (makes red blood cells) and Renin. 

What hormones do the placenta, skin, fat, and thymus make?

Placenta: Estrogen, progesterone, hCG. Skin: Cholecalciferol. Fat (Adipose): Leptin. Thymus: Immune system hormones. 

Which germ layers make steroid vs. amino acid hormones?

Mesoderm: Steroid hormones. Endoderm & Ectoderm: Amino acid hormones

What disorders are caused by Growth Hormone (GH) issues?

Pituitary dwarfism, giantism, and acromegaly. 

What are the main thyroid disorders?

Myxedema, Goiter, Cretinism, Hyperthyroidism, and Grave’s Disease.

What disorders come from the adrenal cortex?

Addison’s Disease (low hormones) and Cushing’s Syndrome (high cortisol).

How do target cells change receptor levels?

Upregulation (adds receptors) and Downregulation (removes receptors).

What membranes cover the digestive organs?

Peritoneum (visceral and parietal). 

What are the four tissue layers of the digestive tract wall?

Mucosa, submucosa, muscularis, and serosa (or adventitia)

What is the function of the mouth?

Ingestion, mechanical chewing, and chemical breakdown. 

How many deciduous (baby) teeth and adult teeth do humans have?

20 baby teeth and 32 adult teeth. 

What are the two muscle types and four papillae types of the tongue?

Muscles: Intrinsic and extrinsic. Papillae: Filiform, fungiform, circumvallate, and foliate. 

What are the three extrinsic salivary glands?

Parotid, submandibular, and sublingual. 

What is the pharynx, and what are the terms for swallowing and chewing?

Pharynx: Common passage for food, air, and fluid. Swallowing: Deglutition. Chewing: Mastication.

What is the outer layer around the esophagus, and does it absorb nutrients?

Adventitia; no, it does not absorb nutrients. 

What is the difference between digestion and absorption?

Digestion breaks food down; absorption takes nutrients into the body. 

What is the difference between mechanical and chemical digestion?

Mechanical is physical breakdown; chemical uses enzymes to break chemical bonds. 

What is a bolus vs. chyme?

Bolus: Chewed food in the mouth. Chyme: Liquefied food in the stomach. 

What do mucus neck cells secrete?

A protective mucous layer. 

What three hormones are secreted by the small intestine (enterogastrones)?

VIP, secretin, and CCK

What are the four main regions of the stomach?

Cardiac, fundus, body, and pyloric region. 

What are the four major secretory cells in gastric pits?

Chief cells, parietal cells, enteroendocrine cells, and mucus neck cells. 

What protects the stomach wall from its acid?

A thick mucous layer. 

What special structural features are in the stomach wall?

Rugae in the mucosa and a modified muscularis layer. 

What are the three parts of the small intestine?

Duodenum, jejunum, and ileum. 

What structures create the brush border in the small intestine?

Circular folds (plicae circulares), villi, and microvilli

What is the digestive role of the liver and hepatocytes?

Hepatocytes in the liver produce bile. 

What is the function of the gallbladder?

it stores bile

What is the purpose of bicarbonate in pancreatic juice?

It buffers the acidic pH of chyme from the stomach.

What cells in the pancreas produce pancreatic secretions?

Acinar cells (acini)

What types of digestion occur in the small intestine?

Both mechanical and chemical digestion.

What are the subdivisions of the large intestine?

Cecum (with appendix), colon (ascending, transverse, descending, sigmoid), rectum, and anal canal. 

What is the main function of the large intestine?

Absorb water and eliminate indigestible matter. 

What three structural features are unique to the large intestine wall?

Haustra, teniae coli, and epiploic appendages.

What are carbohydrates, proteins, and lipids broken down into during chemical digestion?

Carbs: Monosaccharides. Proteins: Amino acids. Lipids: Fatty acids. 

Where does most nutrient absorption happen?

The small intestine. 

What organ is affected by diverticulitis?

the large intestine

How is chemical digestion accomplished?

Through enzymes that break down food into monosaccharides, amino acids, and fatty acids.

Where is the brush border found?

On the microvilli of the small intestine mucosa.

Diverticulitis

Inflammation of pouches in the digestive wall, affecting the large intestine.

What are some problems with the digestive system

Diverticulitis, diarrhea, constipation, hemorrhoids, and appendicitis.

What is a nutrient?

A substance in food that promotes normal growth, maintenance, and repair.

what are the major vs. other nutrients?

Major: Carbohydrates, lipids, and proteins. Other: Vitamins and minerals.

What is the primary use of carbohydrates in the body?

Glucose is the fuel used by cells to make ATP.

All-or-none rule

All amino acids needed must be present for synthesis.

Adequacy of caloric intake

Protein is used as fuel if carbs or fats are insufficient

What are vitamins, how do most function, and which can be synthesized in the body?

Organic compounds that help the body use nutrients, mostly acting as coenzymes. Vitamins D, some B, and K are made in the body.

What are the characteristics of water-soluble vitamins?

Types: B complex and C. Absorbed: With water (B12 requires intrinsic factor). Storage: Not stored in the body.

What are the characteristics of fat-soluble vitamins?

Types: A, D, E, and K. Absorbed: With lipid digestion products. Storage: Stored in the body (except K). (A, C, and E act as antioxidants).

What is a mineral, and how many are required in moderate amounts?

Inorganic elements that work with nutrients for proper function; seven are required in moderate amounts (Calcium, phosphorus, potassium, sulfur, sodium, chloride, magnesium).