Introduction to the Human Body - Chapter 1

Flashcards covering key concepts from the lecture notes on anatomy, physiology, levels of organization, homeostasis, body fluids, feedback systems, and aging.

What is the definition of anatomy?

Anatomy is the study of body structures.

What is the definition of physiology?

Physiology is the study of the function of body structures.

What does the complementarity of structure and function mean?

Structure determines function and function depends on structure (e.g., the nose filters, warms, and humidifies air).

List the levels of structural organization from simplest to most complex.

Chemical, cellular, tissue, organ, organ system, and organismal levels.

What is included in the chemical level of structural organization?

Atoms and molecules.

What is an atom?

The smallest unit of matter that participates in a chemical reaction.

What is a molecule?

Two or more atoms or ions joined by a chemical bond.

What is the cellular level of structural organization?

Molecules form cells; cells are the basic structural and functional unit of life.

What is a tissue?

A tissue is a group of similar cells and the surrounding material that work together to perform a function.

What are the four primary tissue types?

Epithelial, connective, muscular, and nervous tissues.

What is epithelial tissue responsible for?

Covers surfaces, lines cavities, and forms glands.

What is the organ level of structural organization?

Organs are made of two or more different tissue types and have specific functions and recognizable shapes.

Give an example of an organ and its tissue composition.

The stomach is composed of epithelial, connective, and muscular tissues and is involved in digestion.

What is the organ system level?

Organ systems are groups of organs performing a common function (e.g., the digestive system).

What are the functions of the digestive system?

Ingestion of food and liquids, breakdown of food, absorption of nutrients and liquids, elimination of solid waste.

Name some components of the digestive system.

Mouth, pharynx, esophagus, stomach, intestines, anus, teeth, tongue, salivary glands, liver, gallbladder, pancreas.

What is the organism level?

All organ systems work together to maintain homeostasis.

What is homeostasis?

Maintenance of the internal environment within limits.

What is extracellular fluid (ECF)?

Fluid outside cells; part of the internal environment; homeostatic mechanisms regulate its composition and volume.

What is intracellular fluid (ICF)?

Fluid within cells; indirectly maintained by regulating the ECF.

Name examples of body fluids.

Blood plasma, interstitial fluid, lymph, cerebrospinal fluid (CSF), and synovial fluid.

Which systems maintain homeostasis?

The nervous and endocrine systems.

What are the basic components of a feedback system?

Receptor, control center, and effector.

What is a receptor in a feedback system?

Monitors the controlled condition and sends information to the control center.

What is a control center in a feedback system?

Sets the normal range, evaluates input, and sends commands to effectors.

What is an effector in a feedback system?

Receives commands and produces a response that changes the controlled condition.

What is negative feedback?

A mechanism that reverses (negates) a stimulus to return the condition to normal.

What is positive feedback?

A mechanism that reinforces (intensifies) a stimulus until a specific event occurs.

Give an example of negative feedback: maintaining blood pressure.

When BP rises or falls, mechanisms work to return it to normal via baroreceptor signaling and adjustments in heart rate and vessel tone.

Give an example of positive feedback: labor.

Cervical stretching triggers oxytocin release, increasing contractions, which further stretches the cervix until birth.

What is aging and its relation to homeostasis?

Aging is a normal process characterized by a progressive decline in the body’s ability to restore homeostasis.