General Biology : Sir Nico's Materials Animal Tissues Flashcards
All connective tissue is derived from an embryonic tissue known as:
Mesenchyme
Epithelial tissues can be classified according to cell shape.
__________________ epithelial cells are scalelike and flattened.
Squamous
All the following are examples of connective tissue except:
a. bones
b. ligaments
c. neurons
d. tendons
C. Neurons
Of the two major cell types found
in nervous tissue, _________ cells are highly specialized to
generate and conduct electrical signals.
Neurons
How many basic types of muscle tissue are there?
Four
connective tissue,
epithelial tissue,
muscle tissue,
nervous tissue
levels of structural organization
Atom > Chemical Composition > Organelles > Cells > Tissues > Organs > Organ System > Organism
is a sheet of cells that covers
a body surface or lines a body cavity. It
Epithelial Tissue
Based on cell shape, epithelia are classified into three
categories:
- Squamous (scalelike)
- Cuboidal (cubelike)
- Columnar (column-shaped)
epithelia consist of one layer of cells attached to the
basement membrane.
Simple
epithelia consist of two or more layers of cells.
Stratified
Supported by connective tissue. The cells are attached to
and supported by an adhesive
Basement Membrane
There are, in addition, two less easily categorized types of
epithelia.
Pseudostratified Epithelium, Transitional Epithelium
is actually a simple columnar
epithelium (one layer of cells), but because its cells vary
in height and the nuclei lie at different levels above the
basement membrane, it gives the false appearance of being
stratified. This epithelium is often ciliated.
Pseudostratified Epithelium
is a rather peculiar stratified squamous epithelium formed of rounded, or “plump,” cells with the ability to slide over one another to allow the organ to be stretched.
Transitional Epithelium
- Single layer of flattened cells
with disc-shaped central nuclei and sparse
cytoplasm; the simplest of the epithelia. - Allows materials to pass by
diffusion and filtration in sites where protection
is not important; secretes lubricating
substances in serosae. - Kidney glomeruli; air sacs of lungs;
lining of heart, blood vessels, and lymphatic
vessels; lining of ventral body cavity (serosae).
Simple squamous epithelium
Single layer of cubelike cells
with large, spherical central nuclei.
Secretion and absorption.
Kidney tubules; ducts and secretory
portions of small glands; ovary surface.
Simple cuboidal epithelium
Single layer of tall cells with
round to oval nuclei; some cells bear cilia;
layer may contain mucus-secreting
unicellular glands (goblet cells).
Absorption; secretion of mucus,
enzymes, and other substances; ciliated type
propels mucus (or reproductive cells) by ciliary action.
Nonciliated type lines most of
the digestive tract (stomach to rectum),
gallbladder, and excretory ducts of some
glands; ciliated variety lines small bronchi,
uterine tubes, and some regions of the uterus.
Simple columnar epithelium
Single layer of cells of differing
heights, some not reaching the free surface;
nuclei seen at different levels; may contain
mucus-secreting goblet cells and bear cilia.
Secretes substances, particularly
mucus; propulsion of mucus by ciliary action.
Nonciliated type in male’s
sperm-carrying ducts and ducts of large
glands; ciliated variety lines the trachea, most
of the upper respiratory tract.
Pseudostratified columnar epithelium
Thick membrane composed of
several cell layers; basal cells are cuboidal or columnar and metabolically active; surface cells are flattened (squamous); in the keratinized type, the surface cells are full of
keratin and dead; basal cells are active in mitosis and produce the cells of the more superficial layers.
Stratified squamous epithelium
Generally two
layers of cubelike cells.
Stratified cuboidal epithelium
Several cell layers;
basal cells usually cuboidal;
superficial cells elongated
and columnar.
Stratified columnar epithelium
Resembles both stratified
squamous and stratified cuboidal; basal cells
cuboidal or columnar; surface cells dome
shaped or squamouslike, depending on
degree of organ stretch.
Transitional Epithelium
Epithelial Tissues
- Simple squamous epithelium,
- Simple cuboidal epithelium,
- Simple columnar epithelium,
- Pseudostratified columnar epithelium,
- Stratified squamous epithelium,
- Stratified cuboidal epithelium,
- Stratified columnar epithelium,
- Transitional epithelium,
Connective Tissues: Fibers
- Collagen fiber
- Elastic fiber
- Reticular fiber
is composed chiefly of interstitial fluid, cell adhesion proteins, and proteoglycans.
Depending on its specific composition, the ground substance
may be liquid, semisolid, gel-like, or very hard.
Ground Substance
Description: Embryonic connective tissue;
gel-like ground substance containing fibers;
star-shaped mesenchymal cells.
Function: Gives rise to all other connective
tissue types.
Location: Primarily in embryo.
Embryonic connective tissue: mesenchyme
Description: Gel-like matrix with all three fiber
types; cells: fibroblasts, macrophages, mast
cells, and some white blood cells.
Function: Wraps and cushions organs; its
macrophages phagocytize bacteria; plays
important role in inflammation; holds and
conveys tissue fluid.
Location: Widely distributed under epithelia
of body, e.g., forms lamina propria of mucous
membranes; packages organs; surrounds
capillaries.
Connective tissue proper: loose connective tissue, areolar
Description: Matrix as in areolar, but very
sparse; closely packed adipocytes, or fat cells,
have nucleus pushed to the side by large fat
droplet.
Function: Provides reserve fuel; insulates
against heat loss; supports and protects
organs.
Location: Under skin; around kidneys and
eyeballs; within abdomen; in breasts.
Connective tissue proper: loose connective tissue, adipose
Description: Network of reticular fibers in a
typical loose ground substance; reticular cells
lie on the network.
Function: Fibers form a soft internal skeleton
(stroma) that supports other cell types,
including white blood cells, mast cells, and
macrophages.
Location: Lymphoid organs (lymph nodes,
bone marrow, and spleen).
Connective tissue proper: loose connective tissue, reticular
Description: Primarily parallel collagen fibers;
a few elastic fibers; major cell type is the
fibroblast.
Function: Attaches muscles to bones or to
other muscles; attaches bones to bones;
withstands great tensile stress when pulling
force is applied in one direction.
Location: Tendons, most
Connective tissue proper: dense regular connective tissue
Description: Dense regular connective tissue
containing a high proportion of elastic fibers.
Function: Allows recoil of tissue following
stretching; maintains pulsatile flow of blood
through arteries; aids passive recoil of lungs
following inspiration.
Location: Walls of large arteries; within
certain ligaments associated with the vertebral
column; within the walls of the bronchial tubes.
Connective tissue proper: elastic connective tissue
Description: Primarily irregularly arranged
collagen fibers; some elastic fibers; major cell
type is the fibroblast.
Function: Able to withstand tension exerted
in many directions; provides structural
strength.
Location: Fibrous capsules of organs and
of joints; dermis of the skin; submucosa of
digestive tract.
Connective tissue proper: dense irregular connective tissue
Description: Similar to hyaline cartilage, but
more elastic fibers in matrix.
Function: Maintains the shape of a structure
while allowing great flexibility.
Location: Supports the external ear
(auricle); epiglottis.
Cartilage: elastic
Description: Matrix similar to but less firm
than matrix in hyaline cartilage; thick collagen
fibers predominate.
Function: Tensile strength with the ability to
absorb compressive shock.
Location: Intervertebral discs; pubic
symphysis; discs of knee joint.
Cartilage: fibrocartilage
Description: Hard, calcified matrix containing
many collagen fibers; osteocytes lie in
lacunae. Very well vascularized.
Function: Bone supports and protects
(by enclosing); provides levers for the muscles
to act on; stores calcium and other minerals
and fat; marrow inside bones is the site for
blood cell formation (hematopoiesis).
Bones (osseous tissue)
Description: Red and white blood cells in a
fluid matrix (plasma).
Function: Transport of respiratory gases,
nutrients, wastes, and other substances.
Location: Contained within blood vessels.
Blood
Description: Neurons are branching
cells; cell processes that may be quite
long extend from the nucleus-containing
cell body; also contributing to nervous
tissue are nonexcitable supporting cells.
Function: Neurons transmit electrical
signals from sensory receptors and to
effectors (muscles and glands); supporting
cells support and protect neurons.
Location: Brain, spinal
cord, and nerves.
Nervous Tissue
the flesh of the body, is attached to the
skeleton. It is under voluntary control (consciously controlled),
and its contraction moves the limbs and other external body parts. The cells of skeletal muscles are long, cylindrical, non-branching, and multinucleate (several nuclei per cell), with the nuclei pushed to the periphery of the cells; they have obvious
striations (stripes).
Skeletal Muscle
is found only in the heart.
Cardiac Muscle
Cardiac muscle, like skeletal muscle, has striations, but
cardiac cells are branching uninucleate cells that interdigitate (fit together) at junctions called
Intercalated Discs
is found mainly in the walls of hollow
organs (digestive and urinary tract organs, uterus, blood
Skeletal Muscle
