Chapter Review: Tissues and Cellular Responses

Flashcards covering key vocabulary related to muscle tissue, nervous tissue, tissue damage response, and cellular aging and cancer based on the lecture notes.

Myocytes

Muscle cells.

Myoblasts

Individual cells that fuse together to form muscle cells.

Muscle fibers

Connected by connective tissue fascia.

Cardiomyocytes

Individual cardiac muscle cells with single nuclei, striated, forming branching structures, and capped with gap junctions.

Gap junctions

Structures in cardiomyocytes that physically connect and anchor cells, forming channels for metabolic unity, allowing the heart to act as one unit.

Smooth muscle

Reflexive muscle that operates without requiring a brain signal or conscious thought.

Skeletal muscle (identification)

Identified by its straight lines and muscle fibers running parallel to each other.

Cardiac muscle (identification)

Identified by its wavy, branching structures, unique to this muscle type.

Smooth muscle (identification)

Identified by mononucleate cells and a lack of striation.

Nervous tissue

Unique tissue found only in the nervous system, highly specialized for receiving and sending electrical and chemical signals (excitable).

Neurons

Nervous tissue cells responsible for propagating information, forming electrical gradients, and sending electrical signals.

Neuroglia (Glial cells)

Accessory cells in nervous tissue that hold neurons in place, connect them, and regulate concentration gradients around cells.

Dendrites

Parts of a neuron responsible for receiving chemical signals (neurotransmitters) from adjoining neurons.

Neurotransmitter

A chemical substance emitted by one neuron (at the synapse) and picked up by the dendrites of an adjoining neuron.

Myelin sheath

A waxy substance that insulates the axon, aiding in the production and protection of the electrical signal.

Axon

The part of a neuron that sends out signals.

Synapse

The end of the axon where neurotransmitters are released, or the gap between an axon and an adjoining neuron's dendrite.

Action potential

The electrical signal transmitted through a neuron.

Astrocytes

Glial cells that help maintain proper ion concentration and modulate neurotransmitter levels to prevent nervous system overstimulation.

Schwann cells

Glial cells in the peripheral nervous system responsible for forming the myelin sheath around axons.

Oligodendrocytes

Glial cells that secrete the waxy substance forming the myelin sheath (in the central nervous system, analogous to Schwann cells in PNS).

Microglial cells

Immune cells (like macrophages) found in the nervous system that detect and combat pathogens.

Soma

The cell body or 'head' of a neuron, often the easiest part to identify under a microscope.

Four main tissue types

Epithelial, Connective, Muscle, and Nervous tissue.

Inflammation

A common body response to tissue damage, involving vasodilation and increased blood flow to cordon off and repair the damaged area.

Vasodilation

The widening of blood vessels, leading to increased blood flow to an inflamed area, causing redness and swelling.

Mast cells

Cells that release histamine, a primary trigger for the inflammatory response.

Histamine

A chemical trigger for inflammation that brings white blood cells to damaged tissue and increases the permeability of vascular epithelium.

Vascular epithelium

The thin, simple squamous cell lining of blood vessels, which becomes more permeable during inflammation to allow white blood cells to easily pass through.

Pain (inflammation)

An experience during inflammation resulting from the body directing more blood and white blood cells to a damaged location.

Platelets

Primary agents that accumulate around a wound and secrete clotting agents to help repair physical damage.

Clotting agents

Substances released by platelets that attract other platelets and red blood cells, forming a large blood clot.

Fibroblasts (tissue repair)

Cells that rebuild the fibrous matrix around an injury after a clot has formed.

Granular tissue

A temporary, heavily vascularized tissue that forms during tissue repair to redirect blood and nutrients to the injured region, aiding healing.

Scar tissue

Tissue that forms when a blood clot retracts unevenly after injury, potentially becoming visibly prominent.

Atrophy

The loss of mass in muscle and connective tissue, often due to disuse, lack of activity, or aging.

Senescence

The process of biological aging.

Telomeres

Nonsense DNA structures at the ends of DNA strands that act as a protective buffer, preventing the loss of functional DNA during repeated replication.

DNA replication

The process where DNA is copied, during which a small portion of the DNA strand at each end is lost due to the polymerase inability to reach the very ends.

Cancer cells

Cells that multiply uncontrollably, can become invasive, and spread into adjoining tissues, often forming tumors.

Tumors

Collections of cancerous cells, which can be benign (stay in place) or malignant (spread throughout the body).

Hypervascularization of tumors

The process where the body instinctively supplies blood to growing cancer cells, diverting resources from functional tissues.