1. Chapter 28
Overview of Tissues

2. A. The Hierarchy of Structural Organization
Anatomy – structure
Physiology – function
Structure and function are related in Biology.

3. For example: Molecules  cells  tissues  organs  systems  organism
Protein  muscle cell  muscle tissue  heart  cardiovascular system  animal

4. Tissue: similar cells that perform a common function
Organ: structure made of two or more types of tissue that together perform a specific task
Organ system: multiple organs that together perform a vital body function

5. B. Stem Cells
Specialized cells that start off as generic cells and become specialized.

8. C. There are four main types of animal tissues:
Epithelial
Connective
Muscle
Nervous

11. Epithelial tissue: sheets of tightly packed cells that cover body surfaces and line internal organs & cavities
- Cover both inner and outer surfaces of internal organs

12. Layer Cell Shape Location & function
Simple
(single layer)
Squamous
(floor tiles)
capilary and air sac lining
Great for diffusion
Cuboidal
(like dice)
kidney tubules and thyroid gland
secretes
Columnar
(like bricks on end)
intestinal lining
Secretes
Stratified
(more than one)
Skin
Takes a beating/ regenerates fast
sweat and mammary glands
pharynx and anus
Pseudostratified (one layer but looks like more)
upper respiratory

14. 2. Connective tissue binds and supports other tissues
Contains fewer cells, scattered throughout an matrix
Matrix:
Secreted by the cells
Contains a web of fibers embedded in a liquid, jelly, or solid
Non- living
Made from collagen, and elastin
CFLABB

15. Types
Loose connective tissue: binding and packing material to hold organs in place
Fibers are mainly loosely woven collagen and elastic
Fibrous connective tissue: tendons and ligaments
Fibers are densely packed bundles of collagen

16. Adipose tissue: pads and insulates the body and stores energy
Stores fat within cells
Little matrix
Cartilage: shock absorber in joints, nose, and ears
Many collagen fibers embedded in a rubbery matrix

17. Bone: support structure Blood: functions in transport and immunity
Collagen fibers embedded in a hard mineral matrix of calcium, magnesium, and phosphate
Blood: functions in transport and immunity
Consists of cells suspended in a liquid matrix (plasma)
red blood cells (RBCs or erythrocytes)
white blood cells (WBCs or leukocytes)
platelets

18. 3. Muscle tissue functions in movement
Muscle tissue bundles of muscle cells
Most abundant tissue in most animals
In cytoplasm of muscle, large amounts of contractile proteins. (uses ATP from Mito to fuel proteins.)

19. Types Cardiac muscle Skeletal muscle Forms the heart
Cells are striated and branched
Cells connect at specialized junctions for coordinated contraction
Involuntary
Skeletal muscle
Attached to bones by tendons
voluntary body movements
Striped or striated appearance

20. Smooth muscle Lacks striations
Responsible for involuntary organ motions
Ex: intestinal movements (peristalsis)

21. 4. Nervous tissue forms a communication network
Nervous tissue: senses stimuli and quickly transmits information from one part of the animal to another

22. Structure Neuron: Specialized to conduct electrical impulses
Dendrites convey information toward the neuron cell body
Axons convey information away from the neuron cell body
Nervous tissue also includes supporting cells

26. D. Organs made up of tissues
DERNCRIMUILS

27. Organ systems work together to perform life’s functions
Skeletal: supports the body allows movement
Endocrine : secretes hormones to regulate body functions

28. Circulatory: exchanges nutrients, gases, and wastes
Respiratory : exchanges gases with the environment

29. Muscular : produces movement and heat
Integumentary : protects against injury, infection, and dehydration

30. Immune : defends against infection and cancer
Lymphatic : provides fluid balance and immunity

31. Digestive : ingests, breaks down, and absorbs nutrients
Urinary : excretory; removes wastes from the blood

32. Reproductive : initiates and supports developing embryos
Nervous : detects, interprets, and directs response to stimuli

33. E. Animals regulate their internal environment
Regulating both internal & external
An animals internal environment is the interstitial fluid that surrounds the cells.
Internal salt and water balance and blood temperature must be kept stable
Homeostasis: maintaining a “steady state” internal environment
There are always slight fluctuations

34. Homeostasis depends on negative feedback
Negative feedback: a change in a variable triggers mechanisms that reverse that change
Analogous to a thermostat that controls a furnace
Many animal control centers are located in the hypothalamus of the brain
Shivering and sweating are ways of controlling human body temperature