chapter 4 Flashcards
What is a tissue?
A tissue is a group of cells that usually have a common: embryonic origin and function together to carry out specialized activities
There are 4 basic types of tissues in the human body and they are categorized according to their structure and their function
epithelial tissue
covers body surfaces, lines hollow organs, body cavities, and ducts, and forms glands.
tissues that you find on the outside of things
connective tissue
protects and supports the body and its organs, binds organs together, stores energy reserved as fat, and provides immunity.
a lot of types
most diverse type of tissue
muscle tissue
is responsible for movement and generation of force.
made up of small fibers and cells that combine
nervous tissue
initiates and transmits action potentials (nerve impulses) that help coordinate body activities.
epithelial vs connective
epithelial tissue with many cells tightly packed together and little to no extracellular matrix – need strong protection or bacteria would get in – does not have a blood supply – has nerves
connective tissue with a few scattered cells surrounded by large amounts of extracellular matrix – has a blood supply - has nerves
general functions of epithelial tissue
Cells are arranged in sheets and are densely packed
Many cell junctions are present
Epithelial cells attach to a basement membrane
Epithelial tissue is avascular but does have a nerve supply
Mitosis occurs frequently
Connective tissue
very abundant and diverse
-binds things together
supports
strengthens other body tissues
protects and insulates internal organs
serves as the major transport system within the body
contains and distributes almost all of the blood vessels within the body
primary location of stored energy reserves
main source of immune responses
2 elements of connective tissue
cells
extracellular matrix
Connective tissue is highly vascularized and has a
nerve supply
Exceptions: tendons and cartilage - have a poor blood supply and no nerve supply - not able to repair well
matrix
prevents tissue cells from touching one another
can come in fluid, semifluid, gelatinous, fibrous or calcified
high vascularized and has a nerve supply
extracellular matrix
Extracellular matrix is located in the spaces between connective tissue cells
Extracellular matrix is composed of fibers and ground substance
influences cell function
has hyaluronic acid
collagen fibers
Fibers in the extracellular matrix provide strength and support to a tissue
very tough- resistant to stretching– found in bone, tendons, cartilage and ligaments
elastic tissue
reticular fibers
fibers found in skin blood vessels and lungs
-provide support in the walls of blood vessels
strong support around fat cells, nerve fibers and muscle fibers
Embryonic
mesenchyme
mucous
Membranes are
flat sheets of pliable tissue that: cover or line a part of the body
serous membranes
Serous membranes - line body cavities that do not open directly to the outside and cover organs in those cavities
`2 layers, parietal and visceral layer - visceral layer closer to organs. Layer around organ, fluid, then parietal layer
find this in spots where you line the heart, lining the lungs, abdominal cavity and your abdominal organs like your stomach
Mucous membrane
line body cavities that open on the outside and line organs these cavities - all along digestive tract, urinary tract, respiratory and reproductive tracts, variation/modification with ears
Cutaneous membranes
skin covers the surface of the body that contain an articular cavity
top layer epithelium, bottom connective tissue
synovial membranes
line joints that contain an articular cavity
brings nutrients, decreases friction
when not moving a lot, you don’t have a lot of fluid in your joints
Muscular tissue
consists of fibers that provide:motion, maintain posture and produce heat
3 types of muscle tissue
skeletal muscle
cardiac muscle
smooth muscle
Two kinds of cells in the nervous tissue:
neurons
neuroglia
