Chapter 4: Tissue Level of Organization Flashcards
Tissue
a group of cells with specialized activities
Tissues are composed of ___.
Cells and Matrix
The Matrix of tissues can be hard like ___ , semisolid like ___, or liquid like ___.
bone…fat…blood
Cells in most tissues are connected by ___.
junctions
Intracellular Junctions
mechanical connections between cell membranes
Tight Junctions
form a leakproof seal between cells
What is an example of tight junctions?
junctions inside the stomach and bladder to keep materials from leaking out
Adherens Junctions
make an adhesion belt that keeps tissues from separating as they stretch and contract
What is an example of adherens junctions?
cadherin forming the belt-like plaque
Desmosomes
act as spot welds that hook into the cytoplasm
Hemidesmosomes
half welds that join cells to the basement membrane of tissue
Gap Junction
pores that allow ions to pass between cells
What will gap junctions do if the cell gets sick or dies?
it will seal like a hatch to prevent damage to other cells
What are the three primary germ layers?
- Endoderm
- Mesoderm
- Ectoderm
Do epithelial tissues form all three primary germ layers?
YES
What is derived from mesoderm?
Connective tissue and muscle
What tissue develops from ectoderm?
nervous tissue
What are the 4 basic tissue types?
- epithelial
- connective
- muscular
- nervous
Epithelial Tissue
cover body surfaces, form glands and line hollow organs, body cavities, and ducts
What are the three types of epithelial tissue?
- squamous
- cuboidal
- columnar
Connective Tissue
protect, support, and bind organs
4 Examples of Connective Tissue
- fat that stores energy
- red blood cells
- white blood cells
- platelets
Muscular Tissue
generates the physical force needed to make body structures move and generate heat used by the body
Nervous Tissue
detect changes in the body and respond by generating nerve impulses
Epithelium
lines surfaces and forms protective barriers
Epithelium secretes ____, hormones, and other substances.
mucous
True or False: All epithelia have free apical surface and an attached basal surface.
True
The basal layer of the epithelium secretes a ___: the underlying connective tissue secretes a reticular lamina.
basal lamina
What do the basal lamina and reticular lamina form?
basement membrane on which the epithelium sits
Are epithelia named according to cell shape and arrangement of cell layers?
YES
Simple Squamous Epithelium
composed of a single layer of flat cells
Simple Cuboidal Epithelium
composed of a single layer of cube shaped cells
Simple Columnar Epithelium
forms a single layer of column-like cells, cilia, microvilli and mucous
Where is simple squamous epithelium found?
in the air sacs of lungs and the lining of blood vessels, the heart, and capillaries
Where is simple cuboidal epithelium found?
lining of the tubules of the kidneys and many other glands
Goblet Cells
simple columnar cells that can secrete mucous
Stratified Squamous Epithelium
an apical surface that is made up of squamous cells.
True or False: Stratified Squamous Epithelium is composed of many layers.
True
Why do Stratified Squamous Epithelium have many layers?
ideal for protection against strong friction forces
True or False: Connective Tissues are the most abundant and widely distributed tissues in the body.
True
What are 5 function of connective tissue?
- bind tissues together
- support and strengthen tissue
- protect and insulate internal organs
- compartmentalize and transport
- energy reserves and immune responses
What is the most abundant protein in the body, making up about 25% of total protein content, and is the main protein of connective tissue?
Collagen
Connective tissue is usually highly ___ and supplied with many nerves.
vascular
Do cartilage and tendon have blood supply and nerves?
NO