Chapter 20a: Animal Structure and Function Flashcards
What is tissue and what is it made of? What are the four categories of animal tissue?
A group of similar cells that perform a specific function made up of cells, cell junctions, and extracellular material. Includes epithelial tissue, connective tissue, muscle tissue, and nervous tissue.
Look at pics of tissue as you study. Learn to identify and draw the stuctures.
What are the 2 themes in biology that relate to this chapter?
- The diversity of life can be organized in a hierarchy, and emergent properties arise at each level of organization.
- There is a close relationship between structure and function, even at the cellular level.
What is the difference between anatomy and physiology?
Anatomy is the study of an organism’s structure, and physiology is the study of the function of those structures.
Describe the structures and functions of epithelial tissue
Structure:
* sheets of closely packed cells joined by tight junctions (contains nerves, no blood vessels)
* always exposed to air or fluid.
Function:
* Covers body surfaces and lines internal organs and cavities (e.g. epidermis, stomach lining).
* Acts as barrier to mechanical injury, microbial invasion, and fluid loss.
* Some are specialized for absorption and secretion.
All glands are made of epithelial tissue.
Classification of epithelial tissue
-
Cell shape
Cuboidal
Columnar
Squamous -
Number of layers
Simple
Stratified
cuboidal and columnar epithelia are specialized in secretion and absorption (larger internal volume = more space to absorb and release).
Simple Squamous Epithelium
Structure: single layer of flat cells; thin.
Function: specialized for exchanging materials by diffusion.
Location: lung, blood vessels.
Stratified Squamous Epithelium
Structure: several layers of squamous cells.
Function: protection from abrasion, microbial invasion, fluid loss, irradiation.
Location: epidermis (skin), lining the vagina, esophagus, inside of mouth.
These tissue regenerate rapidly
Simple Cuboidal Epithelium
Structure: a single layer of cube-shaped cells.
Function: specialized for absorption or secretion of substances.
Location: kidney tubules (filters blood to urine), thyroid gland, pancreatic ducts.
Non-Ciliated Simple Columnar Epithelium
Structure: a single layer of rectangular cells; may contain microvilli.
Function: speciliazed for secretion (of digestive juices or mucus) or absorption (of nutrients from the intestinal tract).
Location: lining the stomach and intestines.
Microvili are made of microfilaments, meaning they DON’T move.
Ciliated Simple Columnar Epithelium
Structure: single layer of rectangular cells that contain cilia, microtubule extension covered in membrane that move mucus.
Function: protection from microbial infections.
Location: lining respiratory tract and uterine tube.
Cilia made of microtubules, meaning they move.
Transitional Epithelium
Structure: several layers of cells; can change shape- stratified cuboidal (at rest) to stratified squamous (stretched).
Function: provides protection and ability for hollow organs to expand.
Location: urinary bladder, ureters, and urethra.
Describe the Structure and Functions of Connective Tissue
Structure: sparse popultion of cells scattered thoughout extracellular matrix. Cells produce and secrete the ECM with fibers embedded.
Function: make up basic support structure for the body:
* Connects the body’s other tissues in a framework.
* Holds organs in place.
* Attached epithelial to underlying tissues.
Classification of
Connective Tissue
- Loose connective tissue
- Fibrous connective tissue
- Adipose tissue
- Blood
- Bone
- Cartilage
Loose Connective Tissue
Structure: loosely arranged protein fibers and sparse cells.
Function: Acts as glue that binds epithelia to underlying tissues, packs body cavities, and holds organs in place.
Location: surrounding organs in the abdominal cavity, directly underneath skin.
Fibrous Connective Tissue
Structure: densely packed collagen fibers, plus sparse cells.
Function: supports body tissues and provides tensile strength (resists pulling/stretching).
Location: tendons (connect muscle to bone) and ligaments (connect bones to other bones).
Adipose Tissue
Structure: closely packed adopse cells in a sparse matrix of loose fibers and fluid; each adipose cell contains a fat droplet.
Function: store fat; insulates and stores energy.
Location: surround organs.
Cartilage
Structure: collagen fibers embedded in a rubbery matrix, plus cells.
Not vascularized; heals poorly.
Function: absorbs shock.
Location: Nose, ears, trachea, and intervertebral discs.
Bone
Structure: matrix of collagen fibers embedded in a hard substance of calcium salts.
Vascularize, heals relatively quickly.
Function: provides support and protection for the vertebrate body and its organs.
Location: skeleton.
Blood
Structure: cells in liquid matrix called blood plasma (made of water, salts, and proteins).
Function: Red blood cells transport oxygen.
White blood cells have immune functions.
Cell fragments assist in blood clotting.
Describe the Structures and Functions of Muscular Tissue
The most abundant tissue in animals.
Structure: long, excitable cells capable of contraction.
Properties:
Contractibility- ability to shorten with force.
Excitability- capacity to respond to stimuli.
Extensibility- can be stretched beyond resting length.
Elasticity - recoils to original resting length when stretched.
Function: supports body movement and generates heat.
Classification of Muscular Tissue
- Skeletal muscle
- Smooth muscle
- Cardiac
Skeletal Muscle
Structure: striated (striped), long cells with many nuclei, attached to bone.
Function: Responsible for voluntary body movements.
Cardiac Muscle
Structure:striated, branched cells with a single nucleus; joined by thick connections; exclusively heart.
Function: Pumps blood; involuntary.
Smooth Muscle
Structure: NOT striated, spindle-shaped cells with single nucleus.
Function: moves wall of internal organs (e.g. stomach, blood vessels); involuntary.
Describe the Structures and Functions of Nervous Tissue
Structure: Includes neurons (major cells) and supporting cells.
Functions:
* sense stimuli and transmits electrical impulses from one part of the body to another.
* Coordinates and controls body activities.
* Supporting cells provide electrical insulation and nourishment.
Location: Brain and spinal cord.
Neurons, in general, consist of dendrites, a cell body, and an axon.
Cell Junctions
Tight junctions: BInds cells together in a leak proof sheet (ie. bladder, stomach).
Anchoring junctions: Link adjacent cells together (ie. skin).
Gap junctions: Hollow chanels that allows substances to flow between cells (ie. heart cells).
