Animal Body Organization and Homeostasis

Anatomy

Biological structure that varies widely among animals.

Physiology

Biological function closely related to structure; examining anatomy provides insight into physiology.

Cells

Basic units of life.

Tissues

Groups of similar cells performing a common function.

Organs

Structures composed of two or more tissue types.

Organ Systems

Groups of organs that work together in coordination.

Epithelial Tissue

Covers outside of the body and lines internal organs, tightly packed.

Muscle Tissue

Responsible for movement.

Skeletal Muscle

Voluntary movement.

Smooth Muscle

Involuntary activity.

Cardiac Muscle

Specialized for heart contraction.

Connective Tissue

Holds many tissues and organs together; includes blood, cartilage, and adipose tissue.

Nerve Tissue

Involved in information processing and transmission.

Digestive System

Components include mouth, esophagus, stomach, intestines. Function: food processing (ingestion, digestion, absorption, elimination).

Circulatory System

Components include heart and blood vessels. Function: distributes materials internally.

Respiratory System

Includes lungs and trachea. Function: gas exchange (oxygen uptake and carbon dioxide disposal).

Immune and Lymphatic Systems

Main components include bone marrow and lymph nodes. Function: body defense against infections.

Excretory System

Comprises kidneys and ureters. Function: disposes metabolic waste and regulates osmotic balance.

Endocrine System

Includes glands such as the pituitary; coordinates body activities like digestion.

Reproductive System

Involves ovaries or testes. Functions include gamete production and embryonic support.

Nervous System

Contains the brain and spinal cord; coordinates body functions and responses to stimuli.

Integumentary System

Encompasses skin and derivatives; provides protection and thermoregulation.

Skeletal System

Comprises bones and ligaments; supports and protects internal organs.

Muscular System

Consists of skeletal muscles; facilitates locomotion and movement.

Homeostasis

Maintaining a steady internal state despite external changes.

Regulators vs. Conformers

Regulators use internal controls; Conformers adjust to external changes.

Set Points

Organisms maintain variables like temperature and pH around a set point, using sensors and responses.

Negative Feedback

Reduces stimulus (e.g., regulating glucose via insulin).

Positive Feedback

Amplifies stimulus to drive processes to completion (e.g., childbirth).

Acclimatization

Physiological adjustments in response to environmental changes.