Animal Tissues & Organ Systems
Tissues
 Remember our levels of organization/complexity!
 AtomMoleculeCellTissueOrganOrgan
System
 Cytology—Study of cells
 Histology—Study of tissues
Tissues
 Tissue
 A group of similar cells united to perform a specific
function.
 Groups of cells having a similar structure and function
Germ Layers
 Ectoderm—
epidermis, nervous
system
 Endoderm—linings
of digestive &
respiratory tracts, &
associated organs
 Mesoderm—
Skeletal, muscular,
circulatory systems
Tissue Types
 Epithelial
 Connective
 Muscle
 Nervous
Epithelial Tissues
 Line body cavities
 Line body tubes
 Form body coverings
 Form many glands
Epithelial Tissues
 Characteristics
 Closely packed
 Tightly connected
 Polarity


Apical surface
Basal Surface
 Avascular
 Innervated
 High regeneration
Epithelial Tissues
 Classification
 Layers



Simple
Stratified
Pseudostratified
 Shape




Squamous
Cuboidal
Columnar
Transitional
Epithelial Tissues
 Simple Squamous
 Diffusion & filtration
 Kidneys, air sacs, capillaries
 Simple Cuboidal
 Secrete & absorb
 Kidneys, glands, ovaries
Epithelial Tissues
 Simple Columnar
 Absorption, secrete mucus &
enzymes

Cilia on some for propulsion
 Digestive tract (non-ciliated),
bronchi & uterus (ciliated)
 Pseudostratified Columnar
 Secretion, ciliated propulsion
 Respiratory tract, male
reproductive
Epithelial Tissues
 Stratified Squamous
 Protection from abrasion
 Mouth, vagina, skin
Connective Tissues
 Most abundant
 Most diverse
 Extracellular
matrix—nonliving
substance
separating living
cells
Connective Tissues
 Loose connective tissue (fibroblasts)
 Dense connective tissue (fibroblasts)
 Cartilage (chondrocytes)
 Bone (osteocytes)
 Blood (hematopoetic stem cells)
Connective Tissues
 Loose
 Areolar


Connect skin to tissues
Superficial coverings of some
organs
 Adipose



Energy storage
Cushioning
Insulation
Connective Tissues
 Dense
 Irregular—loosely packed



Dermis
Around blood vessels
Part of intestines
 Regular—densely packed


Tendons
Ligaments
Connective Tissues
 Cartilage
 Hyaline


Ends of bone
Ribs to sternum
 Elastic


External ear
Epiglottis
Connective Tissues
 Bone
 30% collagen fibers
 70% mineral salts
 Support & protection
Connective Tissues
 Blood
 55% plasma

Water, proteins, other
 45% cells



Erythrocytes—red blood cells
 Oxygen transport
Leukocytes—white blood cells
 Fight infection
 Clean up debris
Thrombocytes—platelets
 clotting
Muscle Tissues
 Movement
 Highly vascularized
 Actin & myosin microfilaments
Muscle Tissues
 Skeletal muscle
 Multi-nucleated
 Long, parallel fibers
 Striations
 Voluntary contractions
Muscle Tissues
 Cardiac muscle
 Only in the heart
 Branched fibers
 Striations
 Intercalated discs
 Involuntary
Muscle Tissues
 Smooth muscle
 Spindle-shaped fibers
 No striations
 Involuntary
 Blood vessels
 Walls of hollow organs
 Gastrointestinal tract
Nervous Tissues
 Central nervous system
 Brain & spinal cord
 Peripheral nervous system
 Fewest cell types
 Detects, interprets,
transmits, responds to
stimuli
 Coordinates, regulates,
integrates body activities
Nervous Tissues
 Neurons
 Dentrites
 Axons
Nervous Tissues
 Neuroglial cells
 Support & nourish
Tissues to Organs
 Skin
 Epithelial—Stratified
squamous, simple
cuboidal
 Connective—Adipose,
areolar, dense irregular,
blood
 Muscle—Smooth (arrector
pili, blood vessels)
 Nervous
Organ Systems
Organ Systems
Organ Systems
Organ Systems