Unit 1: Introduction, Microscopy and Histology

Magnification of Microscope

objective lens x ocular lens = total magnification

ex: 4.0X × 10X = 40X (survey mode)

ex: 10X x 10X = 100x (low power)

ex: 40X x 10X = 400X (high power)

Parfocal

objects stay in focus with change in objective

Name the Parts of the Microscope

1. ocular lens

2. objective lenses

3. mechanical stage

4. condenser centering screw

5. condenser lens

6. condenser iris diaphragm lever

7. adjustable field diaphragm

8. light source

9. stage adjustment knobs

10. illuminating knob

11. fine focus knob

12. course focus knob

13. objective nosepiece

Microscope Functions

mechanical stage: rests slide, adjusts the position of the slide for viewing

ocular lenses: magnifies to see an image produced by the objective lens

objective lenses: capture incoming light and focus it at the image plane

condenser lens: gathers light and concentrates it into a beam to illuminate an object

iris diaphragm: adjust the amount of light that passes through the condenser

coarse focus knob: brings the specimen into approximate or near focus

fine focus knob: sharpen the focus of the image

light source: creates illumination for the slide

stage adjustment knob: controls the movement of the stage

arm: joins the base to the head and the ocular lens to the base

base: supports the entire microscope sructure

Plasma (Cell) Membrane Definition, Function and Picture

• controls movement into/out of the cell

Cytoplasm Definition, Function and Picture

• a gelatin-like substance, plus structural fibers and organelles that surrounds the nucleus

Nucleus Definition, Function and Picture

• contains the genetic blueprint of the cell

What cells do Microvili live on and what are their functions?

• they live in the G.I. tract

• they live on nonciliated simple columnar epithelium

• increase surface area and is the site of absorption

• looks like finger-like projections on apical surface (doesn’t move)

What cells do Cilia live on and what are their functions?

• ciliated columnar epithelium

• pseudostratified ciliated columnar epithelium

• function is to move products

• found in uterine tube and fallopian tube

• looks like hair-like projections on apical surface (moves)

What cells do Flagellum live on and what are their functions?

• sperm, male reproductive tract

Avascular Def

• without vessels

• all epithelial tissue is avascular

• cartilage and tendons avascular

Vascular Def

• with vessels

• mostly all connective tissue is vascular

Epithelium Def and Functions

• all epithelial tissue has an apical surface and an attached basal surface

• avascular tissue composed of linked cells

• function: lines surfaces and forms protective barrier. also good at secreting things like mucous, hormones and other substances

Basal Surface Def

• attached to underlying CT

Apical Surface Def

• free surface facing the inside of the organ - lumen, or surface of skin

Lumen Def

• space

Goblet Cell Def

• secretes mucus

Merocrine Def

• simplest form of exocytosis; vesicle dumps contents into lumen

• sweat glands, salivary glands, pancreas

Apocrine Def

• apical portion is shed (part of cell gets pinched off)

• mammary glands, sweat glands in armpits and groin

Holocrine Def

• whole cell is lost

• sebaceous glands

Endocrine Def

• exocytosis via basement membrane

Where would you find Simple Squamous Epi. and what does it do?

• lines blood vessels, alveoli of lungs, parts of kidney tubules

• function: absorption, secretion, exchange

• LINES ALL BLOOD VESSELS

Where would you find Simple Cudoidal Epi. and what does it do?

• parts of kidney tubules, ducts of glands, follicles of thyroid gland

• function: absorption, secretion, exchange

Where would you find Simple Ciliated Columnar Epi. and what does it do?

• fallopian tubes (oviducts)

• function: absorption, secretion, exchange

• function of cilia: moves substances across apical surface

Where would you find Simple Columnar Epi. With Microvili and what does it do?

• duodenum (small intestine)

• function: absorption, secretion, exchange

• function of microvili: increases surface area and aids absorption

Where would you find Keratinized Stratified Squamous Epi. and what does it do?

• epidermis of skin

• function: protection, water resistance, resists abrasion

Where would you find Non-Keratinized Stratified Squamous Epi. and what does it do?

• inside of mouth, esophagous, vagina, anus, pharynx

• function: protect from abrasion

Where would you find Stratified Cuboidal Epi. and what does it do?

• sweat glands, mammary glands, salivary glands

• absorption, secretion, exchange

Where would you find Pseudostratified Ciliated Columnar Epi. and what does it do?

• trachea, nasal cavity, bronchi

• absorption, secretion, exchange

Where would you find Transitional Epi. and what does it do?

• bladder, urethra, ureters, renal pelvis

• allows for distension (holds and empties urine)

Mucous, Serous, Cutaneous Def

• mucous: openings to outside

• serous: no openings to outside

• cutaneous: skin

Major Characteristics of Connective Tissue (CT)

• functions: provides support, binds tissues together,

• made up of three parts: cells, fibers, ground substance

Fibroblasts Function

• secrete protein fibers and ground substance

Adipocytes Function

• stores triglycerides

Chondrocytes Function

• make the various cartilagenous C.T.

Osteocytes Function

• make bone

Erythrocytes (RBC)

• transport gases

Leukocytes (WBC)

• immunity

Loose Connective Tissue: Areolar CT Location and Function

• beneath epithelial tissues all over body (deep to epithelium)

• support

Loose Connective Tissue: Adipose CT Location and Function

• subcutaneous layer deep to the skin, around organs and joints

• protection (padding), energy storage, insulation

Loose Connective Tissue: Reticular CT Location and Function

• lymph nodes, spleen, bone marrow, liver kidney

• support

Dense Connective Tissue: Dense Regular CT Location and Function

• tendons, ligaments, aponeuroses

• strength in one direction

• *LOOK FOR FIBERS

Dense Connective Tissue: Dense Irregular CT Location and Function

• dermis of skin, periosteum, capsules of viseral organs, epi- and peri- mysium surrounding cells

• strength in multiple directions

Dense Connective Tissue: Elastic CT Location and Function

• arteries, lungs, skin, periodontal ligament, fetal tissues, connective tissues proper

• stretch and recoil

Where would you find Hyaline Cartilage and what does it do?

• TRACHEA, ends of long bones, between ribs and sternum, nose, larynx, bronchi, embryonic skeleton

• support

• “smoky”

Where would you find Fibrocartilage Cartilage and what does it do?

• pubic symphysis, intervertebral disks, knee joint

• resists compression

Where would you find Elastic Cartilage and what does it do?

• external ear, epiglottis, external auditory meatus

• flexible support

Name the Parts of the Bone

1. central canal

2. lamella (lamellae plural)

3. osteocyte in lacuna (plural lacunae)

4. canaliculi

Name the Components of Blood and Give Their Function

1. erythrocyte

   • transport gases

2. platelet

   • blood clotting

3. plasma

   • remove waste and prevent infection

4. leukocyte

   • immunity

Actin Filaments (Thin Filaments) Function and Location

• function: forming microfilaments

• location: cytoplasm of eukaryotic cells, beneath the plasma membrane

Myosin Filaments (Thick Filaments) Function and Location

• function: muscle contraction

• location: myofibrils

Muscle Tissue Functions and Specific Properties

• produces body movements, maintains posture, generates heat, protects internal organ

• electrically excitable, contracility, extensibility (limited), elasticity

Where would you find Skeletal Muscle and what does it do?

• diaphragm, brachii

• purposeful movement or voluntary movement

  * PERIPHERIAL NUCLEI

Where would you find Cardiac Muscle and what does it do?

• heart

• involuntary contraction of heart

Where would you find Smooth Muscle and what does it do?

• G.I. Tract, walls of organs, ducts, tubes

• involuntary contractions

Nervous Tissue Functions and Characteristics

• integration

• coordination

• derived from Embryonic Neuroepithelium

Where would you find Nervous Tissue, what is it composed of, and what are their functions?

• brain and spinal cord

• composed of:

• cell body (soma) - houses organelles; signal integration

• dendrites - input

• axon - output

• neuroglia - support neurons

What is the difference between grey vs. white matter and where would you find it?

• grey: unmyelinated cell bodies of neurons, neuroglia (inside of spinal cord, outside of brain stem)

• white: myelinated axons, neuroglia (outside of spinal cord, inside of brain stem)

• spinal cord and brain stem

Grey and White Matter in Spinal Cord Picture