Chapter 1: Introduction to Human Anatomy & Physiology

Flashcards covering the definitions, levels of organization, characteristics of life, and homeostatic mechanisms from Chapter 1 of Human Anatomy & Physiology.

Anatomy

The study of the structure of body parts, their forms, and how they are organized.

Physiology

The study of the function of body parts, what they do, and how they do it.

Form follows Function

The concept that a body part's function depends on the way the part is constructed, such as jointed fingers for grasping or the shape of teeth for chewing food.

Levels of Organization

The hierarchical sequence of body components: Atoms → Molecules → Macromolecules → Organelle → Cell → Tissue → Organ → Organ system → Organism.

Organelles

Aggregates of macromolecules, such as proteins, carbs, lipids, and nucleic acids; an example is ribosomes.

Cell

The basic unit of structure and function in the human body.

Tissue

Groups or layers of cells with similar function.

Organs

Groups of tissues that interact to perform a specialized function.

Organ System

Groups of organs that function together.

Organism

A living thing composed of organ systems.

Movement

A change in position of the body or a body part, or the motion of an internal organ.

Responsiveness

The reaction to a change inside or outside the body, for which the brain is most responsible.

Growth

An increase in body size without changing shape.

Reproduction

The production of new cells and new organisms.

Respiration

The process of obtaining oxygen, removing carbon dioxide, and releasing energy from food.

Digestion

The breaking down of food into simpler forms that can be absorbed and used.

Absorption

The passage of substances through membranes and into body fluids.

Circulation

The movement of substances in body fluids.

Assimilation

The process of changing absorbed substances into chemically different forms.

Excretion

The removal of wastes produced by metabolic reactions.

Metabolism

All chemical reactions inside cells; vital signs such as blood pressure and pulse provide insight into this activity.

Water

The most abundant chemical in the body, required for metabolic processes, transportation, and temperature regulation.

Food

Provides the body with chemicals (nutrients), water, energy sources, and raw materials for building living matter.

Oxygen

Constitutes $1/5$ of atmospheric air and is used to release energy from food through aerobic metabolism.

Heat

A product of metabolic reactions that determines the rate of chemical reactions; more heat leads to more rapid reactions.

Fever

A systemic reaction to infection where the Hypothalamus raises the core body temperature to activate immune cells and inhibit bacteria growth.

Atmospheric pressure

The weight of air above and around the body, which is vital for breathing.

Hydrostatic pressure

Also known as blood pressure, it is produced by the heart to force blood through the blood vessels.

Homeostasis

A stable internal environment maintained despite external environmental factors.

Receptors

Homeostatic mechanisms that provide information about the condition of the internal environment.

Set point

A particular value that specifies what a condition should be, such as a body temperature of $98.6$.

Effectors

Muscles or glands that bring about responses to alter conditions in the internal environment.

Negative feedback mechanism

A response to maintain homeostasis where effectors are activated to return conditions to normal and the deviation from the set point progressively lessens.

Hypothalamus

The body's thermostat set at $98.6$; it triggers heat-generating activities like shivering or heat-loss activities like sweating.

Positive feedback mechanism

A process that moves conditions away from the normal state, typically on a temporary basis.