1. Surrounded by selectively permeable membrane– Composed of proteins and lipids– Selectively Permeable Membranes…

• Allow lipid soluble substances to pass easily• Allow small uncharged molecules to pass easily• Allow ions to pass only through protein channels

2. Contains Cytosol3. Contains Organelles with each having

specific functions4. Inclusions5. Exhibit Contact Inhibition6. Differentiated

1. Each has specialized function

The Typical Cell

Cellular CommunicationCellular Communication

Hormone interactions, Foreign Invaders Recognition and

destruction

Electrochemical GradientElectrochemical Gradient

Facilitates intra/extracellular fluids through the membrane via membrane potential

Selective PermeabilitySelective Permeability Regulates entry and exits of cellular materials & Fluids

Permeability depends of four (4) factors

1. Lipid Solubility 2. Size 3. Charge 4. Channels & Transporters

Passive Active (Energy Required) Osmosis Sodium/Potassium Pump Diffusion Vesicular Phagocytosis

Pinocytosis

Osmosis & DiffusionOsmosis & Diffusion

Osmosis DiffusionMovement of water from an

area of high concentration to a low concentration

Movement ions from a high concentration to a low

concentration

Energy Required

ATP

Sodium-Potassium Pump• Ejects 3 Na+ from inside the cell and takes in 2

K +

– Acts as an enzyme to break down ATP for energy required to transport ions across concentration gradients and through the membrane

Integral Protein+ PO4

-

Why is the Sodium Potassium Pump so

Important?

• Maintaining Electrochemcial Gradient and Concentration gradient– Action potential of nerve and muscle

cells– Glucose and Amino Acids into the cell– Movement of Na+ creates a osmotic

gradient that drives the cell’s absorption of water

Exocytosis Exocytosis &&

Endocytosis EndocytosisAnimation

Pseudopods

Phagocytes – Cells designed to perform phagocytosis against invaders and bacterial spores

Examples: Neutrophils (WBC) and Macrophages (Tissues)

• Nucleus – Largest organelle, contains genetic information (chromosomes)

• Ribosomes – Protein synthesis, attached to Rough ER• Rough ER – Storage for new materials to be sent to the Golgi

Complex, responsible for forming glycoproteins. • Smooth ER – Steroid, fatty acid, and phospholipid synthesis• Golgi Complex – Processes, packs, and delivers proteins and

lipids to plasma membrane• Lysosomes – Digestive enzymes which form in the Golgi

Complex• Peroxisomes – Enzymes which oxidize and detoxify many

chemicals in the body primarily the liver and kidney• Mitochondria – Synthesis of ATP (Cellular Respiration

w/glucose)• Cytoskeleton – Filamentous proteins which are responsible for

cellular movement– Microfilaments– Microtubules– Intermediate filaments

• Flagella & Cilia - Movement• Centrioles – Important for forming mitotic spindle during

cellular division

Inclusions

• Melanin– Pigment in hair, skin,

eyes– Screens out harmful

UV rays, can alter appearance AKA suntan

• Glycogen– Quick breakdown for

required energy

• Triglycerides– Stored adipocytes,

broken down to synthesize ATP

I DONT WANT TO GET OLD!

Aging• Progressive degeneration of the body’s homeostatic adaptive

responses– Temperature, Diet, Oxygen Supply

• Geriatrics – Medical field of Elderly care• Signs of Aging

– Gray Hair– Tooth Loss– Wrinkled Skin (Collagen Denaturation)– Decrease in muscle mass– Decrease in osteocyte production

• Osteoperosis• Osteopenia

– Increased Fat deposits– Inability to move

• Due to glucose additions to proteins thus losing the elasticity of body

Cancer Cancer – Severe failure in the regulation of genes (Mutations) that code for cell division

Mutation CausesMutation Causes

Habits

• Alcohol

• Drugs

• Smoking

• Sexual Irresponsibility

Environment• Chemicals (Pesticide, Asbestos,

Benzene)• Second Hand Smoke• UV rays (Sunlight)

Family History• Inherited DNA mutation

Cancer Characteristics• Lack Differentiation

– “Immortal” due to repeated division, normal cells do not repair the mutation

– Not Specialized = No purpose to any body part, does use nutrients from the body

• Have Abnormal Nuclei– - Genes are mutated and contain excessive number of

chromosomes• Form Tumors

– Abnormal mass of cells that invade surrounding tissues and disrupt normal cellular mitosis

Cancer• Cells divide uncontrollably and produce an excess of

tissue– Benign Tumors

• NOT cancerous. • Does not spread to other parts of the body or invade and

destroy nearby tissue. • Benign tumors usually grow slowly.• Generally, not harmful. However, this is not always the case.

If a benign tumor is big enough, its size and weight can press on nearby blood vessels, nerves, or organs, or otherwise cause problems

– Malignant tumor can be fatal• Cancer cells compete with normal cells for nutrients, blood,

and energy eventually causing normal cells to atrophy• The spreading of cancer is known as Metastasis which allows

cells to spread to other parts of the body Cancer cells usually spread via the bloodstream or the lymph system

MelanomaDestruction melanocytes

LymphomaDestruction of lymph nodes

CarcinomaMalignant tumor hat arises from epithelial cells

SarcomaMuscle or connective tissue cancer

LeukemiaDestruction of Leukacytes (WBC)

Necrosis – Death of a cell or a group of cells

Atrophy – Decrease in cellular size and corresponding organs or tissuesNeoplasm – Abnormal formation or

growth

Common Cancer Terms

Biopsy – Removal and microscopic examination of tissues from the body

Viral Associations

Common Viral Diseases• HTLV-1

– Attacks killer T-cells in leukacytes and impairs Lymphatic system

• HIV– Directly attacks Helper T cells which are responsible

for stimulating B Lymphocytes antibody productionEpstein Barr (EBV)– Mononucleosis (Kissing Disease) can attack white

blood cells and lymphatic system (Hodgkin’s Disease)

• Hepatitis B (HBV)– Affects the flow of fluids (bile) through the liver

• Herpes Simplex 2– Cancer of the cervix