Text pages 193-197 Sections 7.4 – 7.6

Text pages 200-209 Sections 7.8 – 7.10

Text pages 87 - 97 Sections 3.5 – 3.8

DURING EMBRYONIC DEVELOPMENT Three Germ Layers

Ectoderm (nervous system, sensory organs, epidermis)

Mesoderm (circulatory system, heart and blood vessels, musculoskeletal, Cartilage, bone marrow, kidney, outer covering of internal organs, gonads, inner skin layer)

Endoderm (inner lining of gastrointestinal tract, respiratory tract, glands liver and pancreas, thyroid, urethra, vagina, lung trachea).

These three germ layers are the embryonic source of all cells of the body. All of the many different kinds of specialized cells that make up the body are derived from one of these germ layers.

Epithelial Tissues cover body surfaces and line body cavities.

Jobs: movement materials in, out, or around the body protection of the internal environment against the external environment, secretion of a product

Come in three basic types: squamous, cuboidal and columnarepidermis (outer part of the skin)Examples: mucosa and serosa that line the body cavities and internal organs, such as intestines, urinary bladder, uterus

The term carcinoma is reserved for malignantgrowth arising from epithelial cells.

Connective tissuesJobs: binding; supporting; protecting; forming blood; storing fats; filling space

Examples: cartilage and adipose, bone and blood)

The most abundant and most widely distributed of all tissues, is found throughout the body.

Malignant tumors of connective tissue (and muscle) are known as sarcomas. Cancers affecting the lymph nodes are called lymphomas,and cancers involving the white blood cells are called leukemias.

Muscle TissueJob: specialized tissue that has both the ability to contract and the ability to conduct electrical impulses.

Examples: Muscles are classified as voluntary or involuntary and as skeletal (striated), smooth, or cardiac

Myosarcoma = malignant tumors

Nervous Tissue Job: forms the communicative pathways, allowing the integrated control of all parts of the body, even parts not directly connected to one another.

Examples: Neurons—motor, sensory, interneuron and glial cells

Malignant cancers: Glioma, Neuroblastoma, Retinoblastoma, Meningeal sarcoma, Anaplastic neurofibroma

Sponges, Cnidarians, Ctenophores, Flatworms and Nematodes

do not have circulatory systems

The cells and body plans of these organismsare set up in such a way

that diffusion and osmosis are effective intransporting oxygen, nutrients and eliminating wastes.

Over a distance of 1 um diffusion occurs in less than one millisecond.

Over a distance of 10 um diffusion occurs in 5 milliseconds.

Over a distance of 1,000 um (1 mm)diffusion takes several minutes.

Circulatory Systems

1) Blood…connective tissue

2) Pump…heart

3) Blood vessels or spaces through which blood circulates

Open Circulatory System

“Heart” pumps blood into vessels with open endsinto spaces called sinuses or hemocoel (blood cavity)

The blood and interstitial fluid (between cells, baths cells, provides a medium for diffusion) are the same.

Blood enters open vessels through openingsIn the “heart”

Mollusks (3 chambered heart)Arthropods (tubular heart)

Hemocyanin (pigment for carrying oxygen)

Closed Circulatory SystemContinuous circuit of blood vessels

…Heart …Blood vessels …Blood …Lymph …Lymph Vessels

Transport nutrients from digestive system to cellsTransport oxygen from respiratory organs to cellsTransport metabolic wastes from each cell toorgans that excrete themTransport hormones from endocrine glands to target cellsHelp maintain body fluid balanceDistribute WBCs, metabolic heat, and buffers

Tubular Circulation

Three varieties of blood vessels:

Arteries = carry blood away from the heart;arterioles

Capillaries = connect the arteries to veins; site of exchange

Veins = carry the blood back to the heartvenules

Elastic, Flexible and Resilient

Muscular walls adjust their diameter

to increase or

decrease blood flow

Fatty materials can build up gradually in arteries

atherosclerosis

http://www.nlm.nih.gov/medlineplus/ency/images/ency/fullsize/18018.jpg

Allow oxygen and nutrients to pass from the blood into tissues

Allow waste products

to pass from tissues into the blood

Extremely thin-walled vessels

Blood flows from the capillariesinto very small veins called venules,

then into the veins that lead back to the heart

Much thinner walls than do arteries;pressure in veins is so much lower

than it is in the arteries

Veins can widen (dilate) as the amount of fluid in them increases

Some have valves in them, to prevent blood from flowing backward.

The main problems inflammation, clotting, and defects that lead to

distention and varicose veins

Pulmonary CirculationSystemic Circulation

1 heart beat takes 0.8 secondsSA node in upper right atriumAV Node in lower right atrium

Heart BeatNervous System Regulates the Heart Beat

Sensory receptors, located in the walls of blood vessels and heart chambers, pick up changes in blood pressure.

Cardiac centers in the Medulla of the brain respond to information provided by sensory receptors

SA node Atrial muscle fibers contract AV node Purkinge fibers in the ventricles stimulated Ventricular muscle fibers contract

Venules Veins Inferior and Superior Vena Cava Right Atrium Tricuspid Valve Right Ventricle Pulmonary Valve (Semi Lunar) Pulmonary Artery

Aterioles Capillaries in Lungs (Alveoli) Venules Pulmonary Vein Left Atrium Mitral valve

Left Ventricle Aortic Valve Aorta Arteries Arterioles Capillaries

Blood FlowPulmonary CirculationSystemic Circulation

Blood Pressure

Nearly 1 in 3 American adults has high blood pressure.High blood pressure can lead to strokes, heart attacks,

and kidney failure.

You can have high blood pressure (hypertension) for years without a single symptom.

A reading below 120/80 mmHg is normal

Blood pressure is the force of the blood pushing against the walls of the arteries.

Results from two forces—by the heart pumping blood into the arteries; and the arteries as they resist the blood flow

systolic (sis-TOL-ik) pressure (heart contracts to pump blood to the body) diastolic (di-a-STOL-ik) pressure (when the heart relaxes between beats)

Men 4.2 – 5.4 million/uL O2 and CO2

Women 3.6 – 5.0 million/uL Life Span 120 days

5,000 – 10,000 uL

150,000 – 400,000 uL Clotting

White blood cells are responsible for the defense system in the body.Colorless without hemoglobin; Life Span 2 or 3 days; Bigger than RBCsThey can change their shape easily and this allows them to squeeze through walls of the blood vessels into the inter-cellular spaces.

RED and WHITE blood cells are formed from the stem cell of the bone marrow.

5 different types of white blood cells

Neutrophils 55%-70% …‘C’ shaped nuclei…Found near sites of infection/injury and in the pus of wounds …Stick to the walls of the blood vessels …Phagocytosis (engulf) foreign particles that try to enter the bloodstream

Eosinophils 2%-5% …Attacks parasites and antigens…Allergic response

Basophils <1% …Secrete anti-coagulant and antibodies …React immediately against external germs and diseases

Monocytes 5%-8% …the largest of WBCs …tissue macrophages (big eaters)…remove foreign particles …prevent the invasion of germs

Lymphocytes 25-35%…produce anti-bodies against toxins secreted by microorganisms…highly specific recognizing certain antigens …anti-bodies cause the foreign bodies and toxins to cluster together which are then engulfed by the phagocytes