Hooke and Zeiss

• Developed and improved compound microscope.
• described plant cell walls 

Positron Emission Tomography

(PET Scan)

• assesses metabolic state
• mechanics: -inject labeled glucose

-electrons colide

-gamma rays given off

• you can see the gulcose usage

1. Observation
2. Question
3. Background Research
4. Hypothesis
5. Experiment
6. Conclusion
7. Was your hypothesis correct

Deductive reasoning to test a hypothesis

1. All organisms composed of cells and cell products
2. Cell is the simplest structural & functions are due to the activities of its cells
3. Cells come only from preexisting cells 
4. Cells of all species have fundamental similarities

Directly connects the cytoplasm of two cells, which allows various molecules and ions to pass freely between cells

Allow chemical and electrical communication btwn cells

-Cells

-Basement membrane (Matrix)

-Cells>Matrix

Layers of closely Adhering cells

Flat sheet with upper surf exposed to enviro of internal body cavity

No blood Vessels

Rests on Basement membrane 

Thin layer of collagen and adhesive proteins

Anchors epithelium to connective tissue

Exchange 

Epithelial cells 

• One cell layer 
• Flattened shape
• Pores btwn cells to permit easy molecule passage
• Lungs & lining of blood vessels

Transporting

Epithelial

cells

• One cell layer
• Columnar or cubodial
• Tight junc to prevent movement; Surf area increased by folding of cell membrane into villi or fingers
• Intestine, kidney, some exocrine glands

Ciliated

Epithelium 

cells

• One cell layer
• Cubodial to columnar
• One side covered with cilia to move fluid across surface
• Nose, trachea, and upper air ways; female repro tract

Protective 

Epithelial

Cells

• Many cell layers
• Flattened in surf layers; Polygonal in deeper layers
• Cells tightly connected by many desmosomes
• Skin, lining of cavities (mouth) that open to enviro

Secretory 

Epithelial

Cells

• One to many cell layers
• Columnar to polygonal
• Protein secreting cells filled with membrane bound secretory granules and extensive RER; steriod secreting cells contain lipid droplets and extensive SER
• Exocrine glands (pancrease, sweat galnds and salivary glands), endocrine glands (thyroid and gonads)

Contains more then one layer

Named by shape of apical cells

Simple Squamous

Epithelium

Singe row flat cells

Permits diffusion

Secretes serous fluid

Aveoli, glmeruli, Endothelium and serosa

Simple Cuboidal

Epithelium

• Single row cube-shaped cells wth microvilli
• Absorption & Secretion, mucus production
• Liver, thyroid, mammary & salivary glands, bronchioles, and kidney tubules

Simple Columnar

Epithelium

• Single row tall, narrow cells
• Oval nuclei in basal half of cell
• Absorption & secretion; mucus secretion
• Lining of GI tract, uterus, kindney & uterine tubes

Pseudostratified 

Epithelium

• Single row of cells some not reaching free surface
• nuclei give layer stratified look
• Secretes & propels respiratory mucus

Keratinized Straified

Squamous Epithelium

• Multilayered epithelium covered with deap squamous cells, packed with keratin
• epidermal layer of skin
• retards with water loss and barrier to organisms
• Heel of foot

Nonkeratinized Stratified 

Squamous Epithelium

• Multilayered surface epithelium forming moist, slippery layer
• tongue, oral mucosa, esophagus and vagina

Stratified cuboidal 

Epithelium

• 2 or more cell layers; surface cells square
• Secretes sweat;produces sperm & hormones
• Swear gland ducts; ovarian follicles and seminferous tubules

Produce thin, watery secretions

Sweat, milk, tears, and digestive juices

Release whole cells 

sperm and egg cells

Consists: Epithelium, lamina propria(areolar connective tissue), muscularis (smooth muscle)

Mucous trap & remove foreign particles & bacteria from internal body surfaces

(Internal membrane)

• Simple spuamous epithelium over areolar tissue, produces serous fluid
• Covers organs & lines walls of body cavities

Developement of endocrine and exocrine glands from epithelium

Protective epithelium 

Widely spread cells separated by matrix(fibers & ground surface)

most abundant & variable tissue type

Func: connects organs, gives support/protection, stores energy & produces heat, movement & transport of materials

Cartilage, bone, blood

Matrix- highly variable

-proteoglycans

-Fibers

Matrix>Cells

Cells-fixed or mobile

White Fibers

-Tough, stretch resistant, yet flwxible

-Tendons, ligaments & deep layer of the skin

Thin, collagen fibers coated wth glycoprotein

Framework in speen & lymph nodes

Thin branching fibers of elastic protein

Stretch & recoil like rubberband

Skin, lungs and arteries stretch & recoil

phagocytize foreign material & activate the immune system

-Arise from monocytes (WBCs)

Gel-like ground substance btwn cells

-Types: areolar, reticular, adipose

-Skin, around blood vessels and organs, under epithelia

-Fibroblast=main cell type

Fibers fill spaces btwn cells

Types vary in fiber orientation

-Dense regular connective tissue

-Dense irregular connective tissue

Fibroblasts=main cell type

Loose arrangement of fibers and cells in abundant ground substance

Underlies all epithelia, btwn muscles, passageways from nerves & blood vessels

Loose network of reticular fibers and cells

Forms supportive stroma (framework) for lymphatic organs 

Found in lymph nodes, speen, thymus & bone marrow

Adipose connective tissue

White: Single lipid droplet

Brown: Multiple lipid droplets

Fibers fill spaces btwn cells

Types vary in fiber orientation

-Dense regular connective tissue

-Dense irregular connective tissue

Densely, packed, parrallel collagen fibers

-compressed fibroblast nuclei

Tendons & ligaments hold bones together & attach muscles to bones

Densely packed, randomly arranged, collagen fibers and few visible cells

-Withstands stesses applied in diff directions

-Deeper layer of skin; Capsules around organs(periosteum)

-Collagen, elastic & reticular fibers, fibroblasts

-Papillary layer (areolar tissue)

-Reticular layer is the deeper part of the dermis (dense irregular tissue)

Extensions of the dermis into the epidermis

-forming the ridges of fingerprints

-allows nerve endings to get close to surface (lips)

-Light and flexible

-No blood vessels

-Supportive connective tissue wth rubbery matrix

-chondroblasts to produce^^matrix

-Trachea and ears

-Rubbery Matrix: dispersed collagen fibers; clustered chondrocytes in lacunae

-supports airway, eases joint movements

-ends of bones at movable joints; sternal ends of ribs; supportive material in larynx, trachea, bronchi & fetal skeleton

-Hyaline cartilage with elastic fibers

-With perichondrium: sheath of dense irregular connective tissue

-Provides flexible, elastic support

-External ear & Epiglottis

-Hyaline cartilage with extensive collagen fibers (never has perichondrium)

-Resists compression & absorbs shock

-Pubic symphysis, meniscus, & intervertabral discs

-Delicate struts of bone

-Covered by compact bone

-Found in heads of long bones

Solid in appearence

-More complex arrangement

-Cells and matrix surround vertically oriented blood vessels in long bones

Bone Tissue

(compact Bone)

-Calcified matrix in lamellae around canal (=osteon)

-Osteocytes in lacunae btwn lamellae

-Bone covered by periosteum

Skeletal support; Leverage for muscles; mineral storage

-Variety of cells/cell fragments; some nuclei & some without

-Ground substance=liquid plasma

-Nonnucleated pale pink cells or nucleated white blood celels

-Found in heart/blood vessels

1. Smooth
2. Cardiac
3. Skeletal

Contractile-force & movement

-Long, cylindrical, unbranched cells: Muscle fibers: with striations & multiple peripheral nuclei

-Movement, facial expression, posture, breathing, speech, swallowing & excretion

Cardiac Muscle

-Short branched cells wth striations & intercalated discs

-One central nuclei per cell

-Pumping of blood by cardiac muscle

-Involuntary

-Short fusiform cells; nonstriated wth only one central nuceus

-Sheets of muscle in visera; iris; hair follicles & sphincters, lining of blood vessles

-Involuntary; Swallowing, GI tract func, labor contractions, control of airflow, erection of hair

-Neurons send signals:

Excitable

Electrical

Chemical

-Glial cells support

-Large cells wth long cell processes, surround by glial cells lacking processes

-Internal communication btwn cells

-In brain, spinal cord, nerves and ganglia

Enlargement of preexisting cells

-Muscle growth through exercise

Unspecialized tissues of embryo become specialized mature types

-Mesenchyme to muscle

Changing from one type of mature tissue to another

-Simple cuboidal tissue before puberty chnages to stratified squamous after puberty (vagina)

Undifferentiated cells wth developmental plasticity

-Emryonic stem cells

-Adult Stem cells

-Totipotent (any cell type possib)

Source = cells of very early embryo

-Pluripotent (Tissue types only possible)

Source = Cells of inner cell mass of embryo

-Multipotent (bone marrow producing several blood cell types)

-Unipotent (only one cell type produced eg epidermis)

Loss of cell size or number

-disuse atrophy from lack of use (leg in cast)

Pathological death of tissue

-Gangrene-insufficient blood supply

-Gas Gangrene- Anaerobic bacterial infection

-Infarction- Death of tissue from lack of blood

-Decubitus Ulcer-Bed sore or pressure sore