Chapter 23: The Structure of Living Things

These flashcards cover key vocabulary from Chapter 23 on the structure of living things, focusing on anatomical concepts, cellular components, and tissue types.

Anatomy

The study of the internal and external body structures.

Physiology

The study of the functions of body structures and how they work.

Pathology

The study of diseases, especially structural and functional changes.

Cytology

The study of cells.

Phospholipid Bilayer

Structure of cell membranes composed of hydrophilic heads and hydrophobic tails.

Carbohydrates

Molecules that supply energy and aid in intracellular structure.

Monosaccharides

Simplest form of carbohydrate; examples include glucose.

Polysaccharides

Complex carbohydrates, such as starches and glycogen, that store energy.

Protein

Large molecules that are essential for structure and function, consisting of amino acids.

DNA

Deoxyribonucleic acid, containing genetic instructions for cellular activities.

RNA

Ribonucleic acid, which converts DNA instructions into proteins.

Homeostasis

The tendency of the system to reach a state of stability and balanced equilibrium.

Metabolism

The process by which chemicals are broken down and used by the body.

Diffusion

Movement of molecules from an area of high concentration to an area of low concentration.

Osmosis

A type of diffusion specifically for the movement of water through a semipermeable membrane.

Active Transport

Movement of molecules against a concentration gradient, requiring energy.

Mitosis

Type of cell division where one cell divides into two identical cells.

Meiosis

Type of cell division resulting in four haploid daughter cells for reproduction.

Epithelial Tissue

Layered sheets of tightly packed cells that provide protection and line organs.

Connective Tissue

Tissue that connects, supports, and protects organs and tissues.

Muscle Tissue

Tissue primarily responsible for movement in the body.

Nerve Tissue

Tissue that transmits and receives electrical signals to facilitate communication.

Lysosome

An organelle containing enzymes that digest food and proteins.

Types of Connective Tissue

• Loose connective tissue (e.g., areolar, adipose)
• Dense connective tissue (e.g., tendons, ligaments)
• Cartilage (e.g., hyaline, elastic, fibrocartilage)
• Bone tissue
• Blood

Types of Muscle Tissue

• Skeletal muscle: Voluntary, striated, attached to bones.
• Cardiac muscle: Involuntary, striated, found in the heart.
• Smooth muscle: Involuntary, non-striated, found in walls of internal organs.

Structure of Nerve Tissue

Primarily composed of neurons (nerve cells) and neuroglia (supporting cells). Neurons consist of a cell body, dendrites for receiving signals, and an axon for transmitting signals.

Structure of Muscle Tissue

Muscle tissue is made of muscle fibers (cells). These fibers contain myofibrils, which are composed of contractile units called sarcomeres. Muscle fibers are organized by connective tissue layers (endomysium, perimysium, epimysium).