Unit 1: Homeostasis & Feedback Mechanisms

Vocabulary flashcards covering key terms and definitions regarding homeostasis, feedback loops, thermoregulation, blood glucose regulation, and body systems from Biology Unit 1 Packet 2.

Homeostasis

The process by which the body maintains a stable internal environment, like keeping temperature and water levels balanced.

Electrolytes

Minerals in your blood and other body fluids that carry an electric charge and affect how your body functions in many ways.

Glucose

A type of sugar that your body uses for energy.

Physiological

Relating to the way in which a living organism or bodily part functions.

Circulatory system

The system of organs and tissues, including the heart, blood vessels, and blood, which carries essential materials to cells and removes waste products.

Cells

The basic structural and functional units of all living organisms.

Coma

A prolonged state of unconsciousness in which a person is unresponsive to their environment.

Phenomena

Observable events or occurrences; facts or situations that are observed to exist or happen, especially when the cause or explanation is in question.

Metabolism

The chemical processes that occur within a living organism in order to maintain life.

Cell respiration

The process by which cells convert glucose into energy, which is essential for sustaining physical activity.

Musculoskeletal system

The framework of the body that holds you together, gives you shape, and enables movement, including bones, muscles, cartilage, ligaments, and tendons.

Skeletal

Relating to or consisting of a skeleton (the bony framework of the body).

Joints

The place where two or more bones meet in the body.

Ligaments

Tough, fibrous bands of tissue that connect bones to each other at joints.

Cartilage

A strong, flexible tissue that covers and protects the ends of bones in joints.

Tendons

Strong cords of tissue that connect muscles to bones.

Minerals

Solid, naturally occurring inorganic substances with a definite chemical composition and crystal structure.

Organs

A part of the body that performs a specific function.

Digestive system

The system responsible for breaking down food into smaller parts for energy, growth, and repair, absorbing nutrients, and eliminating unused waste.

Digestive tract

A continuous tube starting at the mouth and ending at the anus, also called the alimentary canal, measuring about $30\,\text{feet}$ long in an adult.

Mechanical digestion

The physical breakdown of food into smaller pieces, such as through chewing with teeth or the churning of the stomach.

Chemical digestion

The process in which enzymes break down food at the molecular level.

Amylase

An enzyme present in saliva that begins breaking down carbohydrates such as starches and sugars.

Endocrine system

A body system that acts like a messenger service, releasing chemical signals called hormones into the bloodstream to coordinate functions and maintain balance.

Hormones

Chemical messengers that travel through the bloodstream and trigger specific responses in cells that have the matching receptors.

Hypothalamus

The control center of the endocrine system located deep inside the brain that gathers signals and instructs the pituitary gland.

Pituitary gland

A small gland at the base of the brain, often called the master gland, which secretes hormones that control many other endocrine glands.

Glycogen

The form in which glucose is stored for energy within the liver and muscle tissues.

Triglycerides

The form in which fat from food is stored in the human body.

Feedback loop

A circular monitoring system used by the body to maintain homeostasis and dynamic equilibrium.

Negative feedback

A regulatory feedback loop that reverses a directional change to return the biological system to a set point.

Stimulus

A change in the internal or external environment that is detected by a feedback loop.

Sensor (Receptor)

The feedback loop component that detects a stimulus and transmits data to the control center.

Control Center

The feedback loop component that processes sensory signals and issues instructions to an effector.

Effector

The organ or tissue that carries out a homeostatic response to restore balance in a feedback loop.

Insulin

A hormone secreted by beta cells of the pancreas that lowers blood glucose by triggering body cells to take up glucose and inhibiting glycogenolysis.

Glucagon

A hormone released by alpha cells of the pancreas that raises blood glucose concentration by stimulating glycogenolysis and gluconeogenesis in the liver.

Positive feedback loop

A feedback mechanism that amplifies an initial change, moving the system further away from the set point until an endpoint event is reached.