Tissues and Organs (Life Science 1 - Lecture 6)

Flashcards covering the chemical, cellular, and tissue levels of organization, the human organ systems, and the classification of epithelial, connective, muscle, and nerve tissues.

Atom

The smallest stable units of matter, composed of protons, neutrons, and electrons.

Protons

Subatomic particles with a positive electrical charge.

Neutrons

Subatomic particles with a neutral electrical charge.

Electrons

Subatomic particles with a negative electrical charge.

Molecule

A chemical structure held together by shared electrons, such as $O_2$.

Compound

A pure chemical substance made up of atoms of two or more different elements in fixed proportion, such as $NaCl$.

Cellular level

The level of organization involving cells, which are the smallest living units in the body.

Tissue level

The level of organization involving a group of cells working together to perform one or more specific functions.

Organ level

The level of organization involving organs made of two or more tissues working together to perform a specific function.

Organ system level

The level of organization involving a group of organs that interact to perform a particular function.

Organism level

The highest level of organization; an individual life form made up of interacting organ systems.

Integumentary system

An organ system comprising the skin, hair, sweat glands, and nails that protects against environmental hazards and helps regulate body temperature.

Skeletal system

An organ system consisting of bones, cartilage, and ligaments that provides support, stores minerals, and forms blood cells.

Muscular system

An organ system consisting of skeletal muscles and tendons that provides movement, protection, and generates heat.

Nervous system

An organ system that directs immediate responses to stimuli and coordinates the activities of other systems using the brain and spinal cord.

Respiratory system

An organ system that delivers air to the lung alveoli for gas exchange and provides oxygen to the bloodstream.

Cardiovascular system

An organ system that distributes blood cells, water, nutrients, and dissolved gases, and assists in temperature maintenance.

Lymphatic system

An organ system consisting of the spleen, thymus, and lymph nodes that defends against infection and returns tissue fluids to the bloodstream.

Endocrine system

An organ system that directs long-term changes, adjusts metabolic activity, and controls developmental changes via glands like the pituitary and thyroid.

Digestive system

An organ system that processes and digests food, absorbs nutrients, and conserves water.

Urinary system

An organ system that excretes waste products from the blood and controls water balance and blood ion concentrations.

Vertebrate primary tissue types

The four primary categories of tissues: Epithelial Tissue, Connective Tissue, Muscle Tissue, and Nervous Tissue.

Simple epithelium

A classification of epithelial tissue consisting of only one layer of cells.

Stratified epithelium

A classification of epithelial tissue consisting of two or more layers of cells.

Pseudostratified epithelium

A classification of epithelial tissue that consists of one layer but appears to have many.

Cuboidal

Epithelial cells shaped like a cube.

Columnar

Epithelial cells shaped like a column.

Squamous

Epithelial cells that appear flat or squashed.

Connective tissue proper

A class of connective tissue that can be categorized as either loose or dense.

Loose connective tissue

Connective tissue with a large amount of ground substance and a loose scattering of protein fibers like collagen and elastin.

Dense regular connective tissue

Connective tissue where collagen fibers line up parallel to each other, found in tendons and ligaments.

Dense irregular connective tissue

Connective tissue where collagen fibers are arranged randomly, providing a tough covering for organs like the kidneys.

Tendons

Dense connective structures that attach muscle to bone.

Ligaments

Dense connective structures that attach bone to bone.

Cartilage

A robust, flexible special connective tissue made of chondrocytes residing in a ground substance of chondroitin.

Bone

A very strong special connective tissue containing calcium phosphate crystals and osteocytes.

Blood

A special connective tissue consisting of red and white blood cells within a matrix called plasma.

Smooth muscle

Involuntary muscle made of spindle-shaped cells found in the walls of blood vessels and the digestive tract.

Skeletal muscle

Striated, voluntary muscle made of long tubular fibers with multiple nuclei, used for locomotion.

Cardiac muscle

Striated, involuntary muscle consisting of interconnected cells joined by intercalated discs.

Intercalated discs

Gap junctions between cardiac muscle cells that allow them to act as a single functional unit.

Neurons

Nerve cells capable of conducting impulses to deliver information throughout the body.

Dendrites

Highly branched extensions of a neuron that conduct electrical impulses toward the cell body.

Axon

A cytoplasmic extension of a neuron that conducts impulses away from the cell body.

Glial cells

Supporting cells found within nerve tissue alongside neurons.