Tissues

1
Tissues

• Exercise 40

2
Hierarchy of Biology

• Animals coordinate body functions into systems
• Digestive, circulatory, etc.
• These systems are made up of organs
• Circulatory system made up of heart, lungs and
  vessels
• Organs are made up of many different types of
  tissues
• Heart- cardiac muscle, connective tissue

3
Hierarchy of Biology

• Cells with similar structure and function
  constitute a tissue
• There are 4 different types of tissues in the
  body
• Epithelial
• Connective
• Muscular
• nervous

4
Epithelial Tissue

• Epithelial tissue
• Covers the outside of the body and lines organs
  and cavities within the body
• Contains cells that are closely joined with very
  little material between them
• Many types
• Glandular epithelia- secrete or absorb things
• Simple epithelia- single layer of cells
• Stratified epithelia- mulitple tiers of cells
• Can be different shapes- cuboidal, columnar,
  squamous

5
Epithelial Tissue
6
Connective Tissue

• Functions mainly to bind and support other
  tissues
• Contains sparsely packed cells scattered
  throughout an extracellular matrix
• Matrix is fibers embedded in a liquid or
  jelly-like foundation
• Matrix secreted by the connective tissue cells

7
Connective Tissue

• Collagenous fibers- made of collagen, doesnt
  stretch, attach flesh to bone
• Elastic fibers- long threads of elastin, provide
  elasticity of tissues
• Reticular fibers- highly branched collagen, join
  connective tissue to other tissues

8
Connective Tissue

• Most common ones in vertebrates are
• Loose connective tissue-
• Adipose tissue
• Fibrous connective tissue
• Cartilage
• Bone
• Blood

9
Connective Tissue

• Loose connective tissue- Holds other organs in
  place
• Adipose tissue- Stores fat, insulates the body
  and stores energy
• Blood- Transports substances from one part of
  the body to the other
• Fibrous connective tissue- Forms tendons and
  ligaments, joins bones and muscles together
• Cartilage- Surrounds bones, protects them,
  supports nose and ears
• Bone- Support, strong but not brittle

10
Connective Tissue
11
Muscle and Nervous Tissue

• Composed of long cells called muscle fibers
• Capable of contracting when stimulated by nerve
  signals
• Is divided in the vertebrate body into three
  types skeletal, cardiac, and smooth
• Nervous tissue
• Senses stimuli and transmits signals throughout
  the animal

12
Muscle

• Skeletal muscle is responsible for voluntary body
  movements
• Cardiac muscle pumps blood
• Smooth muscle moves the walls of internal organs
  such as the stomach

13
Nervous Tissue

• Forms a communication system that rapidly
  transmits information
• The branching neurons of nervous tissue transmit
  nerve signals that help control body activities
• Cell body and extensions
• Dendrite- conveys signals toward cell body
• Axon- transmits signals away from the cell body

14
Nervous Tissue
15
Muscle and Nervous Tissue