Tissues Flashcards
tissue
collection of similar cells that perform a common function (cells held by junctions)
tight junction
impermeable junction preventing exchange between cells
- digestive tract
adhesion junction
holds cells together despite stretching
- opening of uterus, skin
gap junction
allows communication (small molecules/ions passing from cell to cell)
- beating of cilia, heart, smooth muscle
3 main types of connective tissue
fibrous, supportive, fluid
fibrous connective
loose: open framework
dense: packed together
collagen vs reticular vs elastic fiber
r: branched, thin, forms network
c: unbranched, strong, flexible
e: branched, stretchable
ground substance
fills spaces between cells and fibers
fibroblast
produces fibers + ground substance
mast cell vs stem cell
m: releases chemicals after injury/infection
s: divides to produce other types
supportive connective tissue
cartilage and bone
cartilage
lacunae cell chambers, solid/flexible matrix, low blood supply
hyaline cartilage
fine collagen fibers
elastic cartilage
more elastic fibers (flexible)
fibrocartilage
strong collagen fibers, areas w/high tension/pressure
bone
lacunae chambers, solid/rigid matrix, collagen + calcium salts, vascularized
compact + spongy
Clasts: break down
cytes: maintain
Blasts: building
compact
units called osteons, hard matrix + living cells + blood vessels
eg long shaft bone
spongy
open, latticework w/irregular spaces, surrounds bone marrow cavity
eg ends of long bones
benefits of bone being vascularized
more access to nutrients, growth, and repair
cartilage requires nutrients by diffusion
fluid connective tissue
blood and lymph
blood
fluid matrix (plasma) + 3 formed elements (RBCs, WBCs, platelets)
transfers nutrients and waste to/from tissues
RBCs VS WBCs VS platelets
r: carry oxygen
w: fight infection (immune system)
p: clots blood (pieces of megakaryocytes)
lymph
clear/watery fluid matrix
site of immune system action
lymphatic vessels functions
absorb excess fluids -> cardiovascular system -> absorb fat from small intestine
lymph nodes
(fibrous connective tissue)
“filter” and clean lymph (get enlarged during infections)
muscle tissue
muscle fibers/cells + protein fibers (actin/mysoin) for movement
3: skeletal, smooth, cardiac)
skeletal muscle
long, cylindrical cells, multiple nuclei, striated fibers
attached to bone w/tendon
smooth muscle
spindle-shaped cell w/1 nucleus, lacks striations
walls of hollow organs/vessels
involuntary
slower to contract
cardiac
branched cells w/1 nucleus, strations w/dark striations (intercalated disks) between cells
nervous tissue
communication between cells (sensory input + integration of data + motor output)
neurons + (neuro)glia
neurons
dendrite + cell body + axon
covered in myelin
glia types
oligodendrocytes: form myelin sheath
astrocytes: provide nutrients
microglia: engulf bacteria + debris
epithelial tissue
- tight, continuous network
- lines body cavities, surfaces and glands
- cells anchored by basement membrane (carbs/proteins layer)
- other side exposed to environment
epithelial functions
secretion, absorption, excretion, filtration
epithelial categorization (# of cell layers)
simple: 1
stratified: 1+
pseudostratified: 1 (appears to have more)
epithelial categorization (shape of cell)
cuboidal: cube
columnar: column
squamous: flat
simple squamous
air sacs of lungs, heart and blood vessel linings
exchange of nutrients, gases, wastes
stratified squamous
surface of skin, mouth lining, esophagus
protection against abrasion, infection, drying out
simple cubodial
kidney tubules, glands
absorption, secretion
stratified cubodial
ducts of mammary glands, sweat glands, salivary glands
protection
simple columnar
lining of gut, respiratory tract
absorption, secretion
stratified columnar
rare, urethra
protection, secretion
