chapters 16-20 Flashcards
(32 cards)
What is the primary responsibility of the digestive system?
Breaking down food and absorbing nutrients
The digestive system consists of the digestive tract and accessory organs.
What are the four basic digestive processes?
- Motility
- Secretion
- Digestion
- Absorption
What are polysaccharides broken down into during digestion?
Monosaccharides, mostly glucose
Proteins are digested into what units?
Amino acids and small polypeptides
Fats are digested into which components?
- Monoglycerides
- Free fatty acids
What is the structure of the digestive tract?
A continuous tube from mouth to anus with four layers: mucosa, submucosa, muscularis externa, and serosa
What regulates digestive activities?
- Autonomous smooth muscle function
- Intrinsic nerves
- Extrinsic nerves
- GI hormones
What is the primary site of digestion and absorption?
Small intestine
What role does the stomach play in digestion?
- Storage
- Mixing of food with gastric secretions to form chyme
- Initiation of protein digestion by pepsin
How does the pancreas contribute to digestion?
Secretes digestive enzymes and NaHCO3 to neutralize duodenal acid
What is the function of bile salts secreted by the liver?
Fat emulsification and absorption
What happens in the large intestine?
- Concentrates and stores undigested residues
- Absorbs remaining fluid and electrolytes
- Forms feces
What are the major GI hormones?
- Gastrin
- Secretin
- Cholecystokinin (CCK)
True or False: The digestive tract lumen is considered inside the body.
False
What stimulates gastric emptying?
- Fat
- Acid
- Hypertonicity
- Distension in the duodenum
What are the two classifications of hormones based on solubility?
- Hydrophilic (water-soluble)
- Lipophilic (lipid-soluble)
What is the role of the hypothalamus in the endocrine system?
Controls the pituitary gland
What hormones does the posterior pituitary release?
- Vasopressin (ADH)
- Oxytocin
What does the adrenal cortex produce?
- Mineralocorticoids (aldosterone)
- Glucocorticoids (cortisol)
- Adrenal sex hormones
What role does cortisol play in the body?
Regulates fuel metabolism and stress adaptation
What hormone is secreted by β cells of the pancreas?
Insulin
Fill in the blank: The adrenal medulla secretes _______ in response to sympathetic stimulation.
Epinephrine
What is the primary determinant of the basal metabolic rate of the body?
Thyroid hormone (T3 and T4)
What are the components of the male reproductive system?
- Gonads (testes)
- Reproductive tract (ducts)
- Accessory sex glands
- External genitalia
