Week 3: Tissue Structure & Function Flashcards
Why is tissue level organization so important?
Efficiency
Epithelial Tissue
Lining and covering of tissues.
No blood supply.
3 types.
Squamous
Scale-like.
Flat nucleus.
Epithelial Tissue
Cubodial
Cube shaped
Epithelial
Columnar Cell
Nucleus close to base.
Rectangular shape.
Epithelial Tissue.
Tissue Types in the Body
Connective
Epithelial
Muscle
Nerve
Epithelial Composition
Apical surface on top, attached basal surface on bottom.
Sits on non-cellular basement membrane.
No blood vessels but has nerves.
Replaces itself (regenerative)
Simple Squamous Epithelium: Structure, Function, Location.
One layer.
Thin = easy diffusion.
Reduces friction, diffusion, secretion.
Air sacs of lungs, blood vessels.
Simple Cuboidal Epithelium: Structure, Function, Location.
One layer.
Secretion and absorption.
Ducts of glands and kidneys.
Simple Columnar Epithelium: Structure, Function, Location
One layer.
Microvilli (more surface area)
Secretion and absorption.
Stomach, small intestine, large intestine, digestive glands, gall bladder
Stratified Cuboidal Epithelium: Structure, Function, Location.
Multiple layers.
Secretion and protection.
Sweat glands.
Stratified Squamous Epithelium: Structure, Function, Location.
Multiple layers
Protection of underlying areas subjected to abrasion.
Skin
Stratified Columnar Epithelium: Struc, Fun, Loc
Multiple Layers
Secretion and protection
Male urethra, large excretory ducts of some glands.
Functions of Epithelial Tissues
Protection, permeability, sensation, specialized secretions.
Connective Tissue
Framework of organs/structures by connecting tissues to make up organs.
Composed of Matrix and Associated cells
Matrix
Non-living intercellular material.
Protein fibers and ground substances
Associated Cells (Connective Tissue)
Produce, maintain and are found in matrix.
5 Classifications of Connective Tissue
Loose, Dense, Cartilage, Solid, Liquid
3 Types of Loose
Areolar, Reticular, Adipose
3 Types of Dense
Regular, Irregular, Elastic
3 types of Cartilage
Hyaline, Elastic, Fibrocartilage
Solid Connective
Bone
Liquid Connective
Blood, Lymph
Ground Substance
Fluid, semi-fluid, gelatinuous or calcified
Supports and binds cells.
Fibres
Collagen, elastic, reticular
Types of Connective Tissue Cells
Fibroblasts, Adipocytes, Melanocytes, Leukocytes, Macrophages, Plasma Cells, Mast Cells
Embryonic Connective Tissue
Mesenchyme
Present in embryo and fetus
Soft and delicate fibres
Areolar Connective
Most widely distributed
Contains several types of cells
All fibre types
Strength, elasticity and support.
Function of Areolar
Attaches skin and underlying tissues
Packing between glands, muscles, nerves.
Adipose
Subcutaneous layer of skin and around organs and joints.
Adipocytes for fat storage.
Function of Adipose
Insulation, support, protection, energy reserve.
Reticular
Interlacing reticular fibres and cells
Forms scaffolding used by cells of lymphoid tissues.
Functions of Reticular
Filters/removes old blood cells and microbes in spleen and lymph nodes.
Dense Connective Tissue
Thicker and more dense fibres than loose.
Less cells than loose.
Ex: tendons.
Regular Dense Connective Tissue
Collagen bundles arranged regularly
Fibroblasts in rows between fibres
Forms tendon and ligaments
Strength
Irregular Dense Connective Tissue
Random collagen fibres and fibroblasts
Forms sheets (skin, heart valves, covering of bone)
Strength when forces are pulling from many different directions.
Elastic Dense Connective: Makeup, location, function
Branching elastic fibres and few fibroblasts
Lung tissue, elastic arteries, trachea, bronchi
Allows stretching of organs.
Cartilage: Makeup, location, function.
Collagen fibres and elastic fibres in a dense network.
No blood vessels
Ends of bones, trachea, lungs, nose.
Flexibility and support.
What is the only connective tissue without blood vessels?
Cartilage
Hyaline Cartilage
Most abundant
Lacunae
Ends of long bones, ribs, nose, trachea, bronchi, larynx
Smooth surface for joint movemtn
Elastic Cartilage
Chondrocytes in a threadlike network of elastic fibres
Supportive but bends easily
Part of external ear and epiglottis
Lacunae
Fibrocartilage
Thick bundles of collagen fibres, very strong and tough cartilage.
Discs in intervertebral spaces and knee joints - supports huge loads up and down axis of body.
Bone
Rigid matrix, calcium compounds and collagen fibers.
support, protect, movement
Blood
No fibres
red and white cells
transport and immunity
Skeletal (Striated) Muscle Tissue
Associated with skeleton
Voluntary
Movement, posture, heat production.
Long cylindrical fibres
Cardiac Muscle Tissue
Heart
Involuntary
Circulate blood
Striated, but fibres are branched
Smooth Muscle Tissue
Internal organs and glands
Involuntary
Non-striated
Movement of materials/structure inside body.
Thin spindle shaped cells
Desmosomes
Strong protein structures - hold cells together while the heart contracts
Gap Junctions
On cardiac muscle cells so ions for heart contraction can pass among all cardiac muscle cells.
Intercalated Disc
Dark band between cells
Gap junctions and desmosomes together.
Nervous Tissue
Nerve cells in a loose association forming networkds
Epithelial Tissue overall function
first line of protection from physical, chemical, biological wear and tear.
Connective tissue overall function
connect tissues and organs
Muscle tissue overall function
movement
Nervous tissue overall function
Messages