Lecture: Chapter 04 Flashcards
TISSUES
groups of cells similar in structure that perform a common function
4 TYPES OF TISSUES
1) Epithelial
2) Connective
3) Nervous
4) Muscle
1:
-EPITHELIAL TISSUE-
covers a surface or lines a cavity
EPITHELIAL CLASSIFICATIONS
a)Simple Epithelia=single cell layer; b)Stratified Epithelia=two or more layers stacked; c)Squamous=flat or scale-like; d)Cuboidal=box-like, like a die; e)Columnar=column-shaped, taller than wide
SIMPLE SQUAMOUS EPITHELIUM
Function: diffusion, filtration, secretion
Location: kidney glomeruli; alveoli of lungs; lining of heart, blood vessels, & lymphatic vessels; serosae of ventral body cavity
SIMPLE CUBOIDAL EPITHELIUM
Function: secretion and absorption
Location: kidney tubules, ducts, secretory part of small glands, ovary surface.
SIMPLE COLUMNAR EPITHELIUM
Function: absorption; secretion of mucus, enzymes, & other stuff.
Location: lines most of digestive tract from stomach to rectum
PSEUDOSTRATIFIED COLUMNAR EPITHELIUM
(vary in height, but all cells touch basement membrane; nuclei at different heights, appear to be several layers)
Function: secretion or absorption
Location: sperm-carrying ducts, ducts of large glands, trachea, & most of upper respiratory tract
STRATIFIED SQUAMOUS EPITHELIUM
(2 or more layers; flat, scale-like)
Function: protects underlying tissues
Location: keratinized in epidermis of skin, lining of esophagus, mouth.
STRATIFIED CUBOIDIAL EPITHELIUM
(2 or more layers; cube-shaped)
Function: secretory; sweat glands & mammary glands
Location: boobs and skin
STRATIFIED COLUMNAR EPITHELIUM
Function: protection & secretion
Location: at junctions w/ other types of epithelia: pharynx and male urethra
TRANSITIONAL EPITHELIUM
Function: allows bladder to fill w/ urine, then relax when empty
Location: lining of hollow urinary organs, especially bladder
GLANDULAR EPITHELIA
2 types: Endocrine(ductless) and Exocrine
see following cards
ENDOCRINE GLANDS
“ductless glands;” produce hormones, which are released directly into bloodstream
EXOCRINE GLANDS
secrete their products onto the body surface or into cavities.
(2 types of Glands: uni- and multi-cellular)
UNICELLULAR
excocrine gland
goblet cell (blob-shaped); found in intestinal and respiratory tracts; produce mucin (mucus).
MULTICELLULAR
exocrine gland
2 Parts: epithelium-derived duct & secretory unit;
Structural Classification:
a)Simple(unbranched) or Compound(branched)
b)Tubular(tube-like), Alveolar(flask-shaped), or Tubuloalveolar(both)
Modes of Secretion:
a)Mendocrine=secrete by exocytosis(in pancreas, salivary, & most sweat glands)
b)Holocrine=accumulates product until cell ruptures(sebaceous (oil) glands of skin)
2:
-CONNECTIVE TISSUE-
most abundant & widely spread type of tissue;
3 structural elements: Ground Substance, Fibers, & Cells
GROUND SUBSTANCE
(element of connective tissue)
unstructured material that fills space between cells and fibers
FIBERS
connective tissue
(element of connective tissue)
provide support; 3 types: a)Collagen, b) Elastic, c) Reticular
COLLAGEN FIBERS
mostly collagen (fibrous protein); very high tensile strength; strongest & most abundant by far; *Found in:
ELASTIC FIBERS
mostly elastin (rubbery protein); allow tissue to stretch & recoil; *Found in lungs, bladder, stomach, skin, rectum.
RETICULAR FIBERS
mostly collagen (of a different chemistry); provides support for small blood vessels & organs; *Found in spleen, marrow, liver, kidneys.
CELLS
connective tissue
“blasts”=undifferentiated/immature “baby cells;”
3 types of blasts: a)Fibroblasts-produce connective tissue, b) Chondroblasts-produce cartilage, c)Osteoblasts-produce bone;
Also, Hematopoietic stem cells-produce blood.
“Cyte”=mature/inactive “adult cells”
-TYPES OF CONNECTIVE TISSUE-
Mesenchyme, Connective tissue proper, Cartilage, Bone, Blood, Lymph
(see following cards)
CARTILAGE (class of connective tissue)
3 types: Hyalin, Elastic, Fibro Cartilage
All withstand stretching & compression; all are avascular & receive nutrients by diffusion; no nerve fibers.
HYALINE
type of cartilage
a.k.a. “gristle;” covers ends of long bones, tip of nose; connects ribs to sternum; forms the epiphyseal (growth) plate in growing bones.
ELASTIC
type of cartilage
lots of elastin fibers; external ear, epiglottis.
FIBRO CARTILAGE (type of cartilage)
rows of chondrocytes alternate w/ rows of thick collagen fibers; Found in intervertebral discs, pubic symphysis, and menisci in knees
BONE (class of connective tissue)
supports and protects body structures
BLOOD (class of connective tissue)
made up of cells in nonliving fluid matrix called plasma
LYMPH (class of connective tissue)
extracellular fluid; flows in lymph vessels; similar to blood plasma.
COVERING & LINING MEMBRANES (class of connective tissue)
3 Types: Cutaneous, Mucous, & Serous
CUTANEOUS MEMBRANES
skin
MUCOUS MEMBRANES
a.k.a. “mucosae;” lines body cavities open to the outside; e.g. digestive, respiratory, urogenital tracts - all are moist and secrete mucus.
SEROUS MEMBRANES
a.k.a. “serosae;” found in closed ventral body cavities; produces serous fluid that lubricates facing membranes; named for location: pleura(lungs), pericardium(around heart), peritoneum (abdominopelvic cavity)
3:
-NERVOUS TISSUE-
brain, spinal cord, and nerves; regulates and controls body functions.
2 Major Cell types: Neurons & Supporting Cells
