Lecture Notes Review: Homeostasis, Digestive, and Urinary Systems

Vocabulary flashcards covering homeostasis, feedback mechanisms, and basic digestive and urinary system terms based on the notes.

Homeostasis

The maintenance of a relatively constant internal environment in the body despite external changes.

Stimulus

A change in the environment that initiates a feedback loop.

Receptor

A sensor that detects changes in a variable and sends information to the control center.

Control Center

Usually the brain or spinal cord; decides how to respond to a stimulus.

Effector

An organ or cell that carries out the response to restore balance.

Negative Feedback

A loop that reverses a change to bring a variable back to normal.

Positive Feedback

A loop that reinforces a change, driving processes to completion (e.g., childbirth).

Set Point

The target value at which a variable is maintained.

Blood Glucose (Blood Sugar)

A blood sugar level regulated by hormones to keep energy supply stable.

Beta Cells

Pancreatic cells that sense high blood glucose and secrete insulin.

Pancreas

An organ that produces insulin (endocrine) and digestive enzymes (exocrine).

Insulin

Hormone that prompts body cells to absorb glucose from the blood, lowering blood glucose.

Glucose Uptake

Process of cells taking in glucose from the bloodstream.

Oxytocin

Hormone released by the pituitary that stimulates uterine contractions.

Cervix

Lower part of the uterus; its stretching triggers labor through oxytocin release.

Uterus

Muscular organ that contracts during labor to house the baby.

Labor Loop

Feedback cycle of cervical stretching, oxytocin release, and stronger contractions until birth.

Digestive System

Body system that digests food, absorbs nutrients, and eliminates waste.

Mechanical Digestion

Physical breakdown of food (e.g., chewing, stomach churning).

Chemical Digestion

Enzymatic breakdown of food (e.g., saliva, gastric enzymes, pancreatic enzymes).

Absorption

Uptake of nutrients by the intestinal lining into the blood.

Small Intestine

Primary site of nutrient absorption.

Large Intestine

Absorbs water and forms feces.

Liver

Produces bile to help digest fats.

Gallbladder

Stores and concentrates bile.

Pancreas (Digestive Enzymes)

Produces digestive enzymes (amylase, proteases, lipases) released into the small intestine.

Bile

Digestive fluid produced by the liver and stored in the gallbladder that emulsifies fats.

Mouth

Entry point for digestion; mechanical chewing and chemical saliva begin digestion.

Pharynx/Esophagus

Swallowing pathway that moves food from the mouth to the stomach.

Stomach

Churns food with acids and enzymes to form a digestible substance.

Waste Elimination

Removal of undigested material from the body via the digestive system.

Urinary System

Removes waste from blood and regulates pH, ion balance, and water balance.

Kidneys

Organs that filter blood to form urine.

Ureters

Tubes that carry urine from kidneys to the bladder.

Bladder

Stores urine until it is excreted.

Urethra

Tube through which urine exits the body.

pH Balance

Regulation of the acidity/alkalinity of body fluids.

Filtration

Process by which kidneys filter blood to form urine.

Urine

Fluid excreted by the kidneys.