Unit 4: Tissues Flashcards
what are the main functions of Nervous Tissue?
Rapidly communicates, regulates, and integrates; avascular with virtually no regeneration
What are the two main types of cells in nervous tissue?
Neurons (conducting units) and neuroglia (supportive cells).
What are the three parts of a neuron?
Soma (cell body), axon (transmits impulses away from soma), dendrites (carry impulses to the axon)
What are the two methods of tissue repair?
Regeneration (replacement with the same kind of cells) and fibrosis (scar tissue formation)
Which tissues regenerate easily, poorly, or not at all?
Easy: epithelial tissue, fibrous connective tissue, bone
Poorly: skeletal muscle
No regeneration: cardiac muscle, nervous tissue in brain and spinal cord
what is the main function of muscle tissue?
specialized for movement
name the three types of muscles tissue
skeletal muscle, smooth muscle, and cardiac muscle
what are the characteristics of skeletal muscle?
striated, voluntary, attacked to skeleton, multiple nuclei, parallel arrangement
what are the characteristics of smooth muscle
non-striated, involuntary, found in walls of hollow organs, single nucleus
what are the characteristics of cardiac muscle
striated, involuntary, found in the heart, contains intercalated disc with desmosomes and gap junctions
what is histology
the microscopic study of tissue
what are the two components of tissue
cells (living parts) and matrix (non-living substances)
name the four types of tissues in the body
epithelial, connective, muscle, nervous
what are the three types of cell extensions?
Microvilli (increase surface area), cilia (move substances), flagella (move cells, e.g., sperm)
what are the types of ell junctions
tight junctions (glue), desmosomes (velcro), gap junctions (channels)
what happens during inflammation in tissue repair
inflammatory chemicals increase capillary permeability, allowing clotting proteins to wall off the injured area, forming a clot and eventually a scab
what is granulation tissue
delicate pink tissue formed by new capillaries; phagocytes clear the clot while fibroblast rebuild collagen fibers
what determines whether regeneration or fibrosis occurs in tissue repair
the type of tissue and the severity of the injury
what are the unique features of cardiac muscle cells
Cardiac muscle cells are branched and interconnected, have intercalated discs with desmosomes and gap junctions, creating a functional syncytium where all cells contract together.
What are the distinguishing characteristics of smooth muscle?
Smooth muscle has no striations, is involuntary, and cells are arranged in layers: circular inner and longitudinal outer.
How do skeletal muscle cells differ from cardiac muscle cells?
Skeletal muscle cells are long, cylindrical, striated, voluntary, and have multiple nuclei. Cardiac muscle cells are branched, striated, involuntary, and have specialized cell junctions.
What is the extracellular matrix, and what does it contain?
The extracellular matrix is a non-living substance outside the cell membrane, including extracellular fluids, supporting fibers, and enzymes.
What are the four main types of tissues in the body and their functions
Epithelial: Covers surfaces, lines openings, forms glands.
Connective: Supports and protects, connects tissues, transports substances.
Muscle: Enables movement.
Nervous: Sends and receives electrochemical messages.
How do microvilli aid in cell function?
They increase surface area for absorption, found in the small intestine.
Where are cilia commonly found, and what is their function?
Cilia are found lining the respiratory tract and help move substances over the cell surface.
What is the primary function of skeletal muscle?
Movement of the skeleton
what is the function of smooth muscle in the body
Movement of substance inside hollow organs, such as the digestive system
What are the steps involved in tissue repair?
Inflammation, granulation tissue formation, and regeneration or fibrosis for permanent repair.
what is the role of cardiac muscle
it causes the heart to beat, facilitating blood circulation
What types of tissues have a high capacity for regeneration?
Epithelial tissues, fibrous connective tissues, and bone.
Which tissues are typically replaced with scar tissue during repair?
Cardiac muscle and nervous tissue within the brain and spinal cord.
what are the 3 types of cell junctions
tight, gap, and desmosomes
what does the gap junction do in the cell
allows ions and small molecules to pass directly from the inside of one cell to the inside of a neighboring cell
what does tight junction do in the cell
brings the cells together connecting them together
what does the desmosomes do in the cell
a structure the joins two cells together using protein plaques
what is the texture of cutaneous secretion?
dry, tough, E.g; like skin
what is the texture of serous secretion?
slippery, thin liquid E.G. like water
what is the texture of mucous secretion?
sticky, thick, E.g.; like mucus in your nose
what is the cutaneous membrane in the epithelial tissues
This is your skin, the outermost layer that covers your whole body.
what is the serous membrane in the epithelial tissue
Think of this as a slippery, smooth sheet that covers organs inside your body, like your lungs and heart. It keeps them moist and reduces friction
what is the mucous membrane in the epithelial tissue
Found inside your mouth, nose, and other places that are open to the outside world. It’s moist and sticky because it produces mucus to protect and trap dust or germs.
what is the difference in location where each of epithelial membranes are found
Endocrine
