BIOL 101 Life Processes - Chapter 4: Tissues and Organ Systems

Flashcards covering key vocabulary, definitions, and types of tissues and organ systems as presented in the BIOL 101 Lecture 4 notes.

Tissue

Composed of specialized cells of the same type that perform a common function in the body.

Connective tissue

Diverse in structure and function, composed of specialized cells, ground substance, and protein fibers.

Ground substance

Noncellular material that separates the cells in connective tissue, which may be solid (bone), semifluid (cartilage), or fluid (blood).

Adipose cell

A cell that stores fat.

Stem cell

A cell that divides to produce other types of cells.

Collagen fiber

Unbranched, strong but flexible protein fiber found in connective tissue, providing flexibility and strength.

Elastic fiber

Branched and stretchable protein fiber found in connective tissue, containing elastin, able to stretch to 100x its size without breaking, and providing tissue with flexibility.

Fibroblast

A cell that divides to produce other types of cells, especially collagen and other fibers.

Reticular fiber

Branched, thin collagen fibers that form a delicate supporting network.

White blood cell

A cell that engulfs pathogens or produces antibodies.

Loose fibrous tissue

A type of fibrous connective tissue that supports epithelium in many internal organs, allows organs to expand, and forms protective coverings.

Adipose tissue

A special type of loose connective tissue made of adipocytes that enlarge to store fat, used for energy storage, insulation, and organ protection.

Dense fibrous connective tissue

A type of fibrous connective tissue containing many collagen fibers packed together, making strong, flexible connections between tissues.

Tendons

Dense fibrous connective tissue that connects muscles to bones.

Ligaments

Dense fibrous connective tissue that connects bones to other bones at joints.

Cartilage

Firm, whitish, flexible supportive connective tissue.

Hyaline cartilage

The most common type of cartilage, with a glassy, transparent appearance, found in the nose, at the end of long bones, ribs, and respiratory passages, and forms most of the fetal skeleton.

Elastic cartilage

Cartilage containing a tremendous number of elastin fibers, making it very flexible, found in highly flexible parts of the body like the outer ear.

Fibrocartilage

Cartilage with a matrix containing strong collagen fibers, found in structures that need to withstand tension and pressure like intervertebral disks and the back of the knee joint.

Bone

The most rigid connective tissue, made of a hard matrix of inorganic salts (calcium) deposited around protein fibers.

Osteoblasts

Specialized cells that deposit the bone matrix.

Osteoclasts

Cells that shape the bone matrix to allow bone growth and repair.

Compact Bone

Bone made of cylindrical structural units called osteons, with a central canal surrounded by rings of hard matrix, housing osteocytes, blood vessels, and nerve fibers.

Osteons

Cylindrical structural units that make up compact bone.

Spongy Bone

Bone that appears as an open lattice of irregular bars, plates, and spaces, with solid portions following lines of stress, allowing large vessels and marrow to be housed within.

Blood

A fluid connective tissue performing transport of O2 and CO2, heat distribution, and fluid, ion, and pH balance.

Formed elements (of blood)

Components of blood that include red blood cells (RBCs), white blood cells (WBCs), and platelets.

Plasma

The fluid portion of blood.

Red blood cells (Erythrocytes)

Biconcave, anucleate cells, red due to hemoglobin, which readily binds to oxygen (or carbon dioxide).

Hemoglobin

A pigment in red blood cells containing four iron-rich heme structures, responsible for binding oxygen and carbon dioxide.

White blood cells (Leukocytes)

Nucleated cells involved in immune response, including making antibodies, directly attacking invaders, and producing biochemicals causing inflammation.

Platelets (Thrombocytes)

Fragments of giant cells found in bone marrow that act as patching material to form a plug when a blood vessel is damaged, aiding in clotting.

Lymph

Clear fluid derived from the fluids of surrounding tissues, containing white blood cells, collected by the lymphatic system from interstitial spaces.

Lymph nodes

Structures made of fibrous connective tissue occurring at irregular intervals along lymphatic vessels, serving as a place for WBCs to congregate.

Muscular Tissue

Composed of specialized cells called muscle fibers that contract.

Skeletal muscle

Muscle tissue attached by tendons to bones, under voluntary control, and moves parts of the body.

Striations

Alternating light and dark bands in skeletal and cardiac muscle cells, caused by the placement of actin and myosin filaments.

Smooth muscle

Muscle tissue that moves substances in the lumens of the body, not under voluntary control, and characterized by spindle-shaped cells without striations and a single nucleus.

Cardiac muscle

Muscle tissue found only in the walls of the heart, mostly involuntary, characterized by striations, a single centrally placed nucleus, branched cells, and intercalated discs.

Intercalated discs

Structures that bind cardiac muscle cells end to end, appearing as fused connections.

Nervous Tissue

The central component of the nervous system, composed of neurons and neuroglia.

Neurons

Specialized cells in nervous tissue that conduct nerve impulses.

Neuroglia

Specialized cells that support and nourish neurons, outnumbering them 9:1, and making up over half the brain's volume.

Dendrites

Parts of a neuron that receive signals from sensory receptors or axons of adjacent nerves.

Axons

Extensions of a neuron that conduct nerve impulses, often myelinated (insulated).

Cell body (Neuron)

Part of a neuron that contains most of the cell’s cytoplasm and its nucleus.

Epithelial Tissue

Consists of tightly packed cells forming a continuous layer, covering surfaces and lining body cavities, with protective, secretory, absorptive, excretory, and filtrative functions.

Basement Membrane

A thin layer of carbohydrates and proteins that connects the epithelium to the underlying connective tissue.

Simple epithelia

Epithelial tissue with only a single layer of cells.

Stratified epithelia

Epithelial tissue with layers of cells piled on top of each other, where only the bottom layer touches the basement membrane.

Squamous cells

Flat-shaped epithelial cells.

Cuboidal cells

Cube-shaped epithelial cells.

Columnar cells

Column-shaped epithelial cells.

Simple Squamous Epithelium

Epithelium composed of a single layer of flattened cells, permitting substance exchange, found in blood vessel walls and lung lining.

Simple Cuboidal Epithelium

Epithelium composed of one layer of cube-like cells, frequently found in glands, salivary glands, thyroid, pancreas, ovaries, and parts of the kidney.

Simple Columnar Epithelium

Epithelium composed of one layer of pillar-like cells, lining the digestive tract and uterine tubes.

Pseudostratified columnar epithelium

Epithelium that appears to have two cell layers but does not have true layers, lining the trachea, and sometimes glandular.

Gland

A single or multicellular group of cells that secrete a product onto their outer surface or into a cavity.

Stratified epithelium

Epithelial tissue with layers of cells piled on top of each other, found in the outer layer of the skin, and in cavities of the nose, mouth, esophagus, anal canal, and vagina.

Organ

A group of different tissues performing a common function.

Organ system

A group of organs that perform a common function.

Integumentary system

Protects the body, provides temperature homeostasis, synthesizes vitamin D, and receives sensory input.

Cardiovascular system

Transports nutrients and waste, provides temperature, pH, and fluid homeostasis, and transports hormones.

Lymphatic and immune systems

Defend against infectious diseases, provide fluid homeostasis, and assist in absorption and transport of fats.

Digestive system

Ingests, digests, and processes food, absorbs nutrients, and eliminates waste.

Respiratory system

Exchanges gases at both lungs and tissues, and assists in pH homeostasis.

Urinary system

Excretes metabolic wastes, and provides pH and fluid homeostasis.

Skeletal system

Provides support and protection, assists in movement, stores minerals, and produces blood cells.

Muscular system

Assists in movement and posture, and produces heat.

Nervous system

Receives, processes, and stores sensory input, provides motor output, and coordinates organ systems.

Endocrine system

Produces hormones, coordinates organ systems, regulates metabolism and stress responses, and is involved in fluid and pH homeostasis.

Reproductive system

Produces and transports gametes, and nurtures and gives birth to offspring in females.

Homeostasis

The ability to maintain a relatively consistent internal environment.

Negative Feedback

The primary mechanism by which the body maintains homeostasis, where the body's response to a stimulus is relative in intensity but in the opposite direction, requiring sensors and a control center.

Positive Feedback

A mechanism that brings about change in one direction, where starting signals are increasingly amplified until a process is pushed to completion, requiring sensors and a control center.