(Anaphy 3) Tissues and Membranes

Tissues

A group of similar cells that function together to carry out specialized activities.

Histology

The study of tissues at the microscopic level

Biopsy

A medical procedure in which a small sample of tissue is removed from the body for microscopic examination.

Cell Junctions

Specialized structures that connect cells to each other or to the extracellular matrix.

Cell junction functions

Adhesion, communication, barrier

Main tissue types

Nervous, muscular, epithelial, connective

Nervous tissue

(Tissue) detects changes inside and outside of body → responds by generating nerve impulses → activate muscle contraction

Cells of nervous tissue

Neurons, neuroglia

Nervous tissue locations

Central nervous system (CNS) and Peripheral nervous system (PNS)

Muscular Tissue

(Tissue) Enables movement, force, and contraction; heat generating

Myocytes

All cells found in muscular tissue

Atrophy

Decreased in size or wasting away of a body part or tissue

Muscular tissue types

Skeletal, cardiac, smooth

Skeletal

(Muscular type) voluntary; striated; multi-nucleated; attached to bones via tendons

Cardiac

(Muscular type) involuntary; striated; intercalated discs; heart

Smooth

(Muscular type) involuntary; non-striated; found in digestive tract and blood vessels

Epithelial Tissue

Tightly packed cells with minimal extracellular material; avascular but has nerve supply

Surface

(Epithelial type) body surface and lines hollow organs and body cavities

Layers and shapes of surface epithelium

Simple, stratified, pseudo-stratified; squamous, cuboidal, columnar

Glandular

(Epithelial types) forms glands which produce and secrete substances

Endocrine glands

Type of gland that secretes hormones for metabolic and physiological activities

Exocrine Glands

Type of gland that secretes sweat, oil, earwax, digestive enzymes, and saliva

Epithelial tissue functions

Protection, secretion, excretion, absorption, filtration

Connective Tissue

(Tissue) most abundant and widely distributed; binds organs together; responsible for transportation; protection (bones); blood

Connective tissue cells

Fibers (collagen, elastic, reticular), ground substances

Connective tissue proper

(Connective subtype) loose and dense

LCT types

Areolar, reticular, adipose

Areolar

(LCT type) most common; supports, binds, and cushions organs; found under epithelium; fills spaces between organs

Reticular

(LCT type) networks supporting lymphoid organs (lymph nodes, spleen)

Adipose

(LCT type) fat storage; insulation; energy reserve; found under skin and around organs

Dense regular

(Connective subtype) parallel collagen fibers (tendons, ligaments); strong tensile strength

DCT types

Dense regular, dense irregular, elastic

Dense irregular

(DCT subtype) irregular fiber arrangement for multidirectional strength (dermis)

Elastic

(DCT subtype) high elasticity fiber → allows stretching (arterial walls, bronchial tubes)

Supportive connective

(Connective subtype) structural support, strength

Supportive connective subtypes

Cartilage, bone

Cartilage types

(SC subtype) Hyaline (most abundant), elastic (flexible), fibrocartilage (strongest)

Liquid Connective

(Connective subtype) transportation of nutrients, gases, wastes, and hormones

Bone

(SC subtype) compact bone (dense), spongy bone (lightweight)

Blood

(LC subtype) composed of plasma and formed elements (RBCs, WBCs, platelets); transports nutrients and wastes

Lymph Plasma

(LC subtype) fluid; balance; immunity