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LSC North Harris Biology


Fundamentals of A+P

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Mcgraw- Hill Labeling 		Sanzin's Human Anatomy and Physiology

Unit 3

Cells And Tissues

Unit Objectives:
2. Demonstrate an Understanding of the basic organization of the body
    d. Categorize the relationship of the cell and its functions to the more complex levels of organization within the                 body
  • Four major categories of tissues and their location, structure, and function

Roots of Anatomy

Affix

Meaning

 Affix Meaning Affix Meaning
Cyt-   cell An- Without -glia glue
Endo- within Ana- up Inter- between
Hyper- above Cata- down Macro- large
Hypo- below De- undoing Oss- bone
Inter- between Mut- change Psuedo- false
Iso- equal -zym causing to ferment Squam- scale
Mit- thread Adip- fat Strat- layer
Phag- to eat Chondri- cartilage Exo- outside
Pino- to drink -cyte cell Crist- ridge
-som body Epi- upon -blast budding
Review

Key Terms

Term Definition
Active Transport Process that uses metabolic energy to move a substance across a cell membrane, usually against the concentration gradient.
apoptosis programmed cell death; cell suicide
cell membrane Selectively permeable outer boundary of a cell consisting of a phospholipid bilayer embedded with proteins; also refered to as the plasma membrane or cytoplasmic membrane. 
centromere Portion of the chromosome to which spindle fibers attach during mitosis
centriole Cellualr organelle built of microtubules that organizes mitotic spindle
centrosome Cellular organell consisting of two centrioles
chromatid one-half of a replicated chromosome or a single unreplicated chromosome
chromosome rodlike  structure that condenses  to form chromosomes during mitosis
cytoplasm contenets of a cell, excluding the nucleusand cell membrane
cytoskeleton a system of microfilaments, intermediate filaments, and microtubules provide the cell with structure and shape
differentiation Cell specialization due to different gene expression
diffusion Random movement of molecules  from a region of higher concentration to an area of lower concentration
endocytosis Process by which a cell membrane envelops a substance and draws it into a cell  in a vesicle
endoplasmic reticulum Organelle composed of a system of connected membranous tubules and vescicles along which protein is synthesized. Often reffered to as the  Rough ER or RER. if it has ribosomes present. It is called the smooth ER or SER if ribosomes are not present.
equilibrium State of balance between two opposing forces
exocytosis Transport of substances out of a cell in vesicles
facilitated diffusion Diffusion in which carrier molecules transport substances across membranes from a region of higher concentration to an area of lower concentration
filtration Movement of material across a membrane as a result of hydrostatic pressure
Golgi apparatus An organelle that prepares cellular products for secretion
lysosome organelle that contains digestive enzymes
mitochondrion Organelle housing enzymes that catalyze the reactions of aerobic respiration.
mitosis Division of a somatic cell to form two genetically identical cells
nucleolus Small structure within cell nucleus that contains RNA and proteins
nucleus Cellular organelle enclosed by double layered membrane and conatining DNA; dense core of atom composed of protons and neutrons
organelle Part of a cell that performs a specific function
osmosis Diffusion of water through a selectively permeable membrane in response to a  concentration gradient
phagocytosis Process by which a cell engulfs and digests solid substances; cell eating
pinocytosis Process by which cell engulfs droplets from its surroundings; cell drinking
ribosome Organelle composed of RNA and protein that is a structural support for protein synthesis
selectively permeable Describes membrane that allows some molecules through but not others; semipermeable
vesicle Membranous cytoplasmic sac formed by infolding of the cell membrane
Review
  • cells vary in size from 2 micrometers to over a meter ( like in nerve cells)
  • cells have many different shapes. Some example shapes
    • disk-shaped
    • Some have threadlike extensions
    • toothpick like
    • cube like
    • and many others
  • Cells have many different functions. Some examples:
    • White blood cells wander freely through our body independent of each other. They defend our body from foreign substances like bacteria
    • Some cells make hormones or chemicals to regulate other cells
    • Some help exhange gases in the lungs
    • Some cleanse the blood (kidney tubule cells)
  • Cell Theory:
    • The cell is the unit of structure of all living things
    • The cell is the unit of function of all living things
    • All cells come from pre-existing cells

Anatomy of a Generalized Cell

Remember that all cell types are not exactly like each other, they do often have some basic parts and functions that are common to all cells.
There are three main regions to a cell
  1. nucleus
  2. cytoplasm
  3. plasma membrane

Cell Structure

Location and physical structure

Function
Plasma Membrane External boundary of the cell This confines the cell content.Without this structure, there would be no cell. All cells have this structure and when we say all, we mean prokaryotic, eukaryotic, plant, animal, nerve, connective, etc.... It acts as a door man for the cell controlling what enters and exits the cell. It is also often called the cell membrane or the phospholipid bilayer.
Centrioles Located near the nucleus These direct the formation of the mitotic spindle
Chromatin Dispersed in the nucleus contain the genetic material (DNA);  This coils up to form the chromosomes during the M phase of the cell cycle (mitosis)
Golgi Apparatus often found near the nucleus in the cytosol This organelle packages proteins to be incorporated into the plasma membrane, lysosomes, or prepares them to be exported from the cell.
Inclusions dispersed in the cytosol ( cytoplasm) These provide nutrients; represent cell waste, stored products, etc...
Lysosomes Scattered throughout cytosol These organelles digest ingested materials and worn out organelles. They can also be used to accomplish apoptosis for the cell.
Microvilli Projections of the plasma membrane These extension of the plasma membrane are used to increase the surface area of the cell. Think of a beach towel with a design on it. They often have a smooth side and a rough side. The rough side is better at absorption because it has greater surface area.
Nucleus Large mass, usually at the center of the cell Storehouse for genetic information; The nucleus directs the activites of the cell through protein synthesis.
Nucleolus Dark spherical body in the nucleus Storehouse/ assembly site for ribosomes
Smooth ER In the cytoplasm Site of steroid synthesis and lipid metabolism
Rough ER In the Cytoplasm Transports proteins (made on its ribosomes) to other sites in the cell;  sysnthesizes membrane lipids
Ribosomes Scattered in cytoplasm or attached to RER synthesize protein
Peroxisomes Scattered in cytoplasm Detoxify alcohol; hydrogen peroxide
Crossword Review

Since you have sucessfully completed Biology I, I am not going to spend much time going over the basic cell structure. You are still responsible for knowing about it. You should also review mitosis and meiosis. If my time permits I will add this info to the site, but for now use these resources to review:
 Too much vitamin A or oxygen deprivation can cause the the membrane of the lysosome. This causes the cell to digest itself.

Cell Diversity - Specialized Cells

In this section we will dicuss some of the types of cells built for specific function

  1.  Cells that connect body parts

    • Fibroblast- this type of cell secretes cable-like fibers.  It has plenty of rough ER and large Golgi Apparatus. These structures are necessary to secrete the proteins that are the building blocks of the cable-like fiber structures

  1. Cells that cover and line body organs

    • Epithelial cells - shaped much like the honeycomb of a beehive. This allows the cells to be acked into sheets. It has abundant intemediate filaments that resist being torn when they are rubbed or pulled

  2. Cells that move organs and body parts

    • Muscle cells ( skeletal and smooth) - these are elongated cells with numerous contractile filaments. These filaments are able to contract to move bones or change the size of inernal organs

  3. Cell that store nutrients

    • Fat cells- these conatin a large lipid droplet in their cytoplasm. This results in their large sperical shape.

  4. Cells that fight disease

    • Macrophages- This type of  cell extends large psuedopods to crawl through tissue to reach sites of infection. The lysosomes within the cell digest the microorganisms that it engulfs. A macrophage is a type of  phagocytic cell

  5. Cells that gather information and control body functions

    • Neurons (Nerve cells)- This type of cell is equipped with long processes  for the reception of messages. The cell can then transmit these messages to other structures found in the body. The processes are covered wit an extensive plasma membrane

  6. Cells of reproduction

    • Oocyte (the egg cell)- This is the largest cell in the human body. It contains many copies of all organelles. These are ready to be distributed to the daughter cells that would result from fertilization.
    • Sperm - This long stream lined cell is the Michael Phelps of cells. It is built for swimming. It has a long flagellum that enables it to swim.

Cell Physiology

Most cells have the ability to perform the eight functions essential for life ( see unit 1).

    Cell Division



Body Tissues

Epithelial |  Connective | Muscle | Nervous
  1. Cells are arranged in tissues that provide specific functions for the body.
  2. Cells of different tissues are structured differently, which leads to their differences in function. 
  3. The tissues of the human body include four major types.

uEpithelial Tissues:

Epithelial |  Connective | Muscle | Nervous
General Characteristics of Epithelial Tissue:
  1. Epithelial tissue is widespread throughout the body, covers organs, and lines body surfaces.
  2.  Epithelial tissues are anchored to a basement membrane, are made up of tightly packed cells containing little intercellular material, generally lack blood vessels, and are replaced frequently. 
  3. They function in protection, secretion, absorption, excretion, and sensory reception.

Simple Squamous Epithelium
  1.  Simple squamous epithelium is made up of a single layer of thin, flattened cells.
  2.  Because it is suited for diffusion, it functions in the exchange of gases in the lungs and lines blood and lymph vessels as well as body cavities.



Simple Columnar Epithelium
  1. Simple columnar epithelium is made up of a row of elongated cells whose nuclei are all located near the basement membrane.  It may be ciliated.
  2. It lines the uterus, stomach, and intestines where it protects underlying tissues, secretes digestive fluids, and absorbs nutrients.
  3. In the intestine, these cells possess microvilli that increase the surface area available for absorption.
  4. Mucus-secreting goblet cells can be found among columnar cells.

Pseudostratified Columnar Epithelium
  1. These cells appear layered due to the varying positions of their nuclei within the row of cells, but are not truly layered.
  2. Cilia may be present, along with mucus-secreting globlet cells, that line and sweep debris from respiratory tubes.

Stratified Squamous Epithelium
  1. This type of tissue is made up of layers of flattened cells that are designed to protect underlying layers.
  2. It makes up the outer layer of skin, and lines the mouth, throat, vagina, and anal canal.
  3. In the skin, outer layers of cells undergo keratinization; however, this process does not occur where tissues remain moist in the throat, vagina, or anal canal.

Stratified Cuboidal Epithelium
  1. This tissue consists of two to three layers of cuboidal cells lining a lumen of the mammary glands, sweat glands, salivary glands, and pancreas. 
  2. Several layers of cells provide greater protection than one single layer.

Stratified Columnar Epithelium
This tissue consists of several layers of cells and is found in the vas deferens, part of the male urethra, and parts of the pharynx.

Transitional Epithelium
  1. Transitional epithelium is designed to distend and return to its normal size, as it does in the lining of the urinary bladder. 
  2. This design provides distensibility and keeps urine from diffusing back into the internal cavity.


Glandular Epithelium
1. This tissue is made up of cells designed to produce and secrete substances into ducts or into body fluids.
2. Glands that secrete products into ducts are exocrine; those that secrete into body fluids and blood are called endocrine.
3. Glands are classified by the ways the glands secrete their products.
  • a. Merocrine glands release fluid products by exocytosis (pancreas) and are grouped as serous which produce a watery fluid or mucus which produce a thicker, protective substance.
  • b. Apocrine glands lose portions of their cell bodies during secretion (mammary glands). 
  • c. Holocrine glands release entire cells (sebaceous glands).




Connective Tissues:

Epithelial |  Connective | Muscle | Nervous

A. General Characteristics

  1. Connective tissues bind, support, protect, serve as frameworks, fill spaces, store fat, produce blood cells, protect against infection, and repair tissue damage.
  2. Unlike epithelial tissues, connective tissues have abundant matrix, or intercellular material, throughout, and have good blood supplies (except cartilage).

B. Major Cell Types

  1.  The fibroblast is the most common cell type, and is a fixed, star-shaped cell that secretes fibers and is large in size. 
  2.  Wandering macrophages function as scavenger cells and defend against infection.
  3.  Mast cells are large and are located near blood vessels where they release heparin (anticoagulant) and histamine (promotes inflammation).

C. Connective Tissue Fibers

  1. Strong collagenous fibers (white fibers), made of the protein collagen, add strength for holding body parts together.
  2. Elastic fibers (yellow fibers), made of the protein elastin, are stretchy and add flexibility to certain types of connective tissues.
  3. Reticular fibers are thin collagenous fibers that form supportive networks in a variety of tissues.

Types of Connective Tissue

Loose Connective (areolar) Tissue

  1. This type of tissue forms delicate, thin membranes throughout the body that bind body parts together such as skin and underlying organs.
  2. The majority of the cells are fibroblasts that are separated by a gel-like ground substance that contains collagenous and elastic fibers.

Adipose Tissue

  1. Adipose tissue is loose connective tissue designed to store fat. 
  2. It is found beneath the skin, around joints, padding the kidneys and other internal organs, and in certain abdominal membranes.

 Dense Connective Tissue

  1. This tissue consists of densely packed collagenous fibers and is very strong but lacks a good blood supply. 
  2.  It is found as part of tendons and ligaments.
  3. Cartilaginous structures are enclosed within a connective tissue perichondrium.
  4. The most common, hyaline cartilage, is white with abundant fine collagen fibers, is found at the ends of bones, and supports respiratory passages.
  5. Elastic cartilage, with elastic fibers, provides a framework for the external ears and parts of the larynx.
  6. Fibrocartilage, with many collagenous fibers, is a tough tissue that provides a shock-absorbing function in intervertebral disks and in the knees and pelvic girdle.

Bone

  1. Bone is the most rigid connective tissue, with deposits of mineral salts and collagen within the matrix. 
  2.  Bone internally supports the body, protects, forms muscle attachments and is the site for blood cell formation.
  3. Bone cells, called osteocytes, lie within lacunae and are arranged in concentric circles (osteons) around osteonic canals interconnected by canaliculi. 
  4. Bone has a good blood supply, enabling rapid recovery after an injury.

Blood
  1. Blood is composed of cells (red and white) suspended in a liquid matrix called plasma.
  2. It functions to transport substances throughout the body.

Muscle Tissues:

Epithelial |  Connective | Muscle | Nervous
 General Characteristics
  •   Muscle cells, or fibers, can contract and consist of three major types.

Skeletal Muscle Tissue

  1. Skeletal muscle is attached to bone and can be controlled by conscious effort (voluntary). 
  2. The cells (muscle fibers) are long and cylindrical, striated, have many nuclei and contract from nervous impulse.

Smooth Muscle Tissue

  1. 1. Smooth muscle tissue lacks striations, is uninucleate, and consists of spindle-shaped cells.
  2. 2.This involuntary muscle is found in the walls of internal organs, and in the digestive tract, blood vessels, and urinary bladder.  

Cardiac Muscle Tissue

  1. Cardiac muscle tissue is found only in the heart and consists of branching fibers that are connected to each other with intercalated disks.
  2. This involuntary muscle has a single nucleus in each cell but appears striated.

Nervous Tissues:

Epithelial |  Connective | Muscle | Nervous
  1. Nervous tissues are found in the brain, spinal cord, and nerves.
  2. Neurons, or nerve cells, conduct nervous impulses while helper cells, or neuroglia, support and nourish the neurons.




Quizzes:


Tissue Matching Excercise:
http://www2.lbsdk12.com/science/Anatomy/tissuematchingexcercise.htm

Chapter 4 from Barron's Anatomy and Physiology The Easy Way questions 1-20
http://www2.lbsdk12.com/science/Anatomy/hapeasywaych4120.htm

Fill in the Blank Quiz
http://highered.mcgraw-hill.com/classware/ala.do?alaid=ala_733401

Histology Photos
http://science.nhmccd.edu/BioL/tissue.html

Tissues of the Human Body
http://www.mhhe.com/biosci/ap/histology_mh/start_histology.html

Histology Slides
http://www.meddean.luc.edu/lumen/MedEd/Histo/frames/histo_frames.html

Histology Practical
http://www.gwc.maricopa.edu/class/bio201/histoprc/prac1q.htm

Goblet Cells
http://arbl.cvmbs.colostate.edu/hbooks/pathphys/misc_topics/goblets.html

Epithelia Study Guide
http://cellbio.utmb.edu/microanatomy/epithelia/epith_lec.htm