1. Animal Tissues and Organ Systems
Chapter 20

2. Key Concepts Types of tissues Organ systems
Four tissues types organized into organs
Epithelial
Connective
Muscle
Nervous
Organ systems
Three embryonic tissues are source of all adult organs
Each organ system has specialized function

3. Stem Cells
Undifferentiated cells with potential to develop into many cell types
Embryonic stem cells, more versatile
Adult stem cells, less versatile

4. Body Organization Tissue Organ Organ system
Group of cells performing same task
Organ
Two or more tissues performing same task
Organ system
Two or more organs performing same task

5. Tissues
Groups of cells and intercellular substances that interact in one or more tasks
Example: muscle tissue

6. Organs Group of tissues organized to perform a task or tasks
Example: Heart is an organ that pumps blood through body
Heart consists of muscle tissue, nervous tissue, connective tissue, and epithelial tissue

7. Organ Systems
Groups of organs that interact physically and/or chemically to perform a common task
Example: Circulatory system includes heart, arteries, and other vessels that transport blood through the body

8. Homeostasis Stable operating conditions in the internal environment
Brought about by coordinated activities of cells, tissues, organs, and organ systems

9. 4 Types of Tissues Muscle tissues Nervous tissues Epithelial tissues
Connective tissues
Muscle tissues
Nervous tissues

10. Type 1: Epithelial Tissues
Sheet-like, line body surfaces, cavities, ducts, and tubes
One free surface faces a body fluid or the environment
simple
squamous
epithelium
basement
membrane
connective tissue

11. Secretory organs derived from epithelium
Glands
Secretory organs derived from epithelium
Exocrine glands have ducts or tubes
Salivary and sweat glands
Secrete to the OUTSIDE
Endocrine glands are ductless
Adrenals and pituitary
Secrete to the INSIDE
exo = out endo = in

12. Type 2: Connective Tissues
Most abundant tissues in the body
Different types
Soft
Beneath skin, encapsulates organs
Specialized
Cartilage
Bone
Adipose (fat)
Blood
Fibroblasts
Secrete “ground substance” forming polysaccharides
Secrete collagen, the most abundant protein in the human body

13. Soft Connective Tissues
Loose connective tissue
Dense, irregular connective tissue
Dense, regular connective tissue

14. white blood cell
platelet
red blood cell
Fig. 20-3g, p.342

15. Type 3: Muscle Tissue Cells contract when stimulated
Moves body and specific body parts
2 types, 3 classes
Striated
Skeletal
Cardiac
Not striated
Smooth

16. Skeletal Muscle Attaches to and moves bones Long, cylindrical cells
Striated cells
Voluntary control
nucleus

17. Cardiac Muscle Present only in heart Cells are branching
Ends joined by communication junctions
Cells striated
Not under voluntary control
where cells meet

18. Smooth Muscle Located in soft internal organs and blood vessels
Cells taper at ends
Cells not striated
Not under voluntary control
cell nucleus

19. Type 4: Nervous Tissue
Detects stimuli, integrates information, and relays commands for response
Consists of excitable neurons and supporting neuroglial cells

20. This allows the cells to:
Neurons
“Excitable” cells
This means that:
Stimulus sends electrical impulse along plasma membrane because of specific proteins
This allows the cells to:
Transmit information to other neurons, muscles or glands

21. Neuron Anatomy

22. 11 Major Organ Systems Integumentary Nervous Muscular Skeletal
Circulatory
Endocrine
Lymphatic
Respiratory
Digestive
Urinary
Reproductive
I promise that you will be tested on these 11 systems. At the very least, you will need to know the functions of each system. All of this info is on page 344.

23. 11 Major Organ Systems Integumentary System Nervous System
Muscular System
Skeletal System
Circulatory System
Endocrine System
Fig. 20-6, p.344a1

24. 11 Major Organ Systems Lymphatic System Respiratory System
Digestive System
Urinary System
Reproductive System
Fig. 20-6a2, p.344

25. Skin: An Organ System Integumentary
Epidermis: Stratified epithelium
Dermis: Dense connective tissues
Hypodermis: Loose connective tissue and adipose tissue

26. Functions of Human Skin
Protects body from injury, dehydration, UV radiation, and some pathogens
Helps control temperature
Receives external stimuli
Involved in vitamin D production
Important stuff, this

27. Sun Damages Skin UV light stimulates melanin production
tans skin
Tan protects inner layers against UV damage
UV exposure causes
elastin fibers to clump
skin to age prematurely
skin cancer

28. The Epidermis is an Epithelial Tissue
Porphyria and vampirism

29. Where do Tissues and Organ Systems Come From? Primary Tissues
Three primary tissues in vertebrate embryos give rise to all adult tissues:
Ectoderm
Mesoderm
Endoderm
ecto=out meso=middle endo=inside

30. Primary Tissues (cont’d)
Ectoderm
Outer layer of skin
Nervous tissue
Mesoderm
Muscles, bones and most of the circulatory, reproductive and urinary systems
Endoderm
Lining of the digestive tract, as well as the liver, lungs and pancreas

31. 5 Major Body Cavities Cranial cavity Spinal cavity Thoracic cavity
Abdominal cavity
Pelvic cavity