Will Stephan Pass Bio 33?

QUIT MAKIN' FACES AT ME!!!

2006-05-04T08:25:00.000-07:00

Facial Nerves

Facial nerves leave the brain stem and weave their way thru the temporal bone through the internal acoustic meatus, coming out through the stylomastoid foramen to reach the face.
The noive,er,NERVE then goes to five of the facial muscles:
A. the temporal,
B. the zygomatic,
C. the buccal,
D. the mandibular and
E. the cervical muscles.
These are all somatic motor neurons.
(image courtesy of http://www.meddean.luc.edu/lumen/MedEd/GrossAnatomy/h_n/cn/cn1/mainframe.htm)

The facial nerve is mixed, since besides motor neurons, they are also parasympathetic and sensory. The parasympathetic motor impulses go to:
- lacrimal (tear) glands
-nasal and paltine glands
-submandibular and sublingual salivary glands

(image courtesy of http://tmjc.com.ne.kr/tmj/info/drinfo/tmjneed7.htm)

As far as senses go, sensory inpulses come from the tongue(first two-thirds of it.)
The facial nerve is tested sensory-wise by giving the subject sweet, salty, sour and bitter substances. The motor neuron efficiency is tested by asking the subject to close eyes, smile, whistle(which i never learned to do, uh oh, i'd fail this one), and so on. Tearing is tested by using ammonia fumes on the subject, or withholding the treat i was promised for taking part in this test.

Out on an (Upper) Limb

2006-04-07T20:49:00.000-07:00

(Image courtesy of Stephan Rose,Esq.)

Instead of doing my blog today, i'd rather work out in BCC's lovely fitness center and try to get these slim arms of mine a big bigger! This has been a challenge for me, since my biceps seem the least likely of my body parts to take to weight-lifting! I think i'll do some curls...

The upper arm is made up of one bone,the humerus aka the funny bone(NEVER funny when you hit it,though). It's the larger and longest bone of the upper limb. It is attached to the scapula (shoulder) at one end, and the forearm at the other. The forearm is composed of two bones, the ulna (which is most prominent at the elbow) and the radius. At the end of the forearm that isn't attached to the upper arm(duh) is the hand. First the carpus aka wrist is composed of eight marble-sized bones. Further up the hand we have the palm,composed of the five metacarpal bones, small long bones. Our fingers are made up of the phalanges, three per fingers,except for the pointer finger, which only has two.

Synovial, the One-and-Only-al

The one joint found everywhere in the upper limb is the synovial joint. All the bones connected by synovial joints have a fluid-filled cavity between them. This joint offers the most freedom of movement. The five features of a synovial joint are *tympani drum* :

1. Hyaline cartilage (glassy-looking and smooth)covers the ends of the opposing bones. They are spongy and absorb compression. BOING!
2. A joint cavity filled with synovial fluid(how easy to remember!)
3. The cavity is surrounded by a two-layer capsule. The outer layer is tough,composed of dense connective tissue(strengthens), and the inner layer is made of loose connective tissue. It is called the synovial membrane, and it covers all internal joint surfaces that don't have hyaline cartilege on them.
4. The aforementioned synovial fluid fills all the space in the capsule. This thick and sticky liquid gets thicker as it warms up, as when the joint is being used. It reduces friction between the cartileges and has phagocytic cells that keep the cavity free of microbes and cell debris.
5. Ligaments strengthen and reinforce the synovial joints.

Usually where you find synovial joints, you find bursae. They are 'bags of lubricant' that reduce friction. They are flat sacs lined with a synovial membrane and synovial fluid inside of that. Tendon sheaths is a kind of longer bursa that wraps completely around a tendon, protecting it from friction.

The five TYPES of synovial joints are : plane, pivot,condyloid,saddle and ball-in-socket. All are found in the upper limb.

MUSKLES!

There are five main muscles in the upper limb: the triceps brachii, the anconeus, the biceps brachii, the brachialis, and the brachioradialis. The first two are found on the back of the arms, the next three on the front. (Brachi is Latin for "arm".)

The triceps have three heads, originate on the scapula and backside of the humerus, and insert by a tendon on the ulna. They extend the forearm, extend against resistance,and works opposite the forarm flexors.

The anconeus is the elbow muscle, short and triangular, originates on the humerus and ends on the ulna. It works with the triceps when extending the elbow muscle, and moves the ulna away from the body when the forearm is pronated (palm facing down).

(Image taken from http://www.fun-and-fitness.com/mus-zone.)

The biceps is a two-headed muscle that originates on the scapula and inserts on the radius. They flex the elbow and turn the palm facing back (supinated forearm),flexes the arm at the shoulder somewhat.

The brachialis is a strong muscle originating on the front of the humerus and inserting on the ulna and flexes the forearm. When the biceps lift the radius, it lifts the ulna!

(Image taken from http://www.fun-and-fitness.com/mus-zone.)

The brachioradialis is the topmost muscle on the outside of the forearm, originating on the humerus and inserting on the radius. It helps flex the forearm, and during radid flexing and extending, it stabilizes the elbow.

The forearm muscles are called flexors, and they move the fingers and the wrist.

Three Cords to Hold You, Five Nerves to Love You

(Image courtesy of http://depts.washington.edu/anesth/regional/brachialplexusanatomy.html.)

The brachial plexus is half in the neck,half in the armpit aka axilla and eventually becomes three cords or large fiber bundles: the lateral, the medial and the posterior cords. They then divide into five main nerves: axillary, musculocutaneous,median,ulnar and radial. The axillary innervates the deltoid and teres minor muscles, the musculocutaneous supplys motor fibers to the biceps and brachialis, the median activates the wrists,fingers and turns the palm down, the ulnar innervates most of the hand muscles and the forearm, and the radial innervates all the extensor muscles.

Put It All Together,It Spells...

Peripheral does NOT mean "of minor relevance or importance"!

2006-03-16T19:43:00.000-08:00

Peripheral Nerves...what do they do? Where can you find them? Do they owe you any money? Let's find out the answers,shall we?The object in question, peripheral nerves!(courtesy the University of Kansas)

The peripheral nerve system is your body's link to the outside world. It consists mostly of bundles of axons that extend from the brain and spinal cord(both of which make up the CENTRAL nervous system). The peripheral nevers from the brain are call cranial, and the ones from the spine are called spinal.All these nerves link all body parts to the CNS. The PNS has two subdivisions, but it's all the SAME thing. (wakka wakka) The Sensory aka Afferent division is nevres fibers carring messages TO the central nervous sysytem from sensory receptors anywhere on the body. The Motor or Efferent division brings impulses from the CNS to muscles and gland, also known as effector organs (as in,they EFFECT a response).
The sensory division is split into two categories. Fibers conveying information from the skin, joints and skeletal muscles, are called somatic afferent, and those bringing impulses from visceral organs are called visceral afferent fibers(visceral=ventral body cavity).
The motor division has two categories within itself. The somatic nervous sytem (soma means "body") which is composed of axons (aka nerve fibers) which we have conscious control over, and the automatic nervous sytem composed of visceral motor nerve fibers that controls glands, cardiac and smooth muscles. Guess why it's call automatic? cause we don't have to think about it! that's right,ladies and gentlemen..it happens by itself. Thus, it is sometimes called the "involuntary nervous sytem."
Look,ma! It's an automatic nervous system!(photo courtesy of the University of Delaware)

Nervous tissue is made up of two kinds of cells: supporting cells which surround and wrap more delicate neurons, and...neurons! They transmit electrical signals.
Neurons hang out with smaller cells called neuroglia. Think of them as "nerve glue". The two types of neuroglia found in the PNS are satellite cells and Schwann cells. Satellites surround the neuron cell bodies. They look like moons around a planet! Schwann cells surround and form sheaths around larger nerve fibers.

Got Spine?
(Photo coutesy www.spineuniverse.com)

What is the Peripheral Nerve System without the vetebral column? Um,a big nasty mess!

The spine aka vetebral column is about 28 inches long in an adult, S-shaped, and have five major divisions. The first 7 vertebrae are the cervical(supporting the neck), the next 12 are the thoracic, and the ones supporting the lower back are called lumbar. The book suggested something really corny to remember how many vertebrae are in each section: common meals times are at 7 am, 12 noon,and 5 pm. Corny,but it works for me! Under the lumbar, we have the sacrum, which is 5 vertebrae fused together, and the coccyx aka "tailbone", which is four fused vertebrae. The vertebral column surrounds the spinal cord, keeping it safe. And how does Mr Spine work with Mr PNS?

Remembering that the Central Nervous System includes the brain and spinal chord, from the brain projects 12 pairs of cranial nerves, and from the spinal cord, 31 pairs of spinal nerves. All of these pairs of nerves are referred to as the Peripheral Nervous System. Of the spinal nerves, 8 come from the cervical area, 12 from the thoracic, 5 from the lumbar, 5 from the sacrum,and only one from the coccyx. Each spinal nerve connects to the spinal cord by means of roots: one to the front of the spine,one to the back. The front or ventral roots have the motor fibers, and the rear or dorsal roots have the sensory fibers.
(Photo courtesy of http://www.unm.edu/~jimmy/spinal_notes.htm)

Tissue? I don't even KNOW y...aw,forget it.

2006-02-11T07:27:00.000-08:00

Okay, kids...today,tissue is the issue.

There are two main types of tissues that we will discuss today (sorry muscle and nervous..you just don't rate!) These types are Epithelial and Connective.

Epithelial has you covered. Specifically, it covers your external body (epidermis),lines cavities and tubules, separates our insides from our outsides. The epithelium protects, absorbs, filters, excretes and secretes,and recieves the senses.
The two main types of epithelial tissue are:

1. Simple (just one layer)
2. Stratified (two or more layers)

For simple epithelia, we have four categories, named according to shape:

1. Squamous (think "squashed")
2. Cuboidal (cubelike)

3. Columnar (column-shaped)

4. Pseudostratified which LOOKS like more than one layer of cells, but it's just cells of all different heights with nuclei at various heights,also.

For stratified epithelia, it's pretty much just multi-layered versions of categories one through three, with the fourth type being Transitional epithetlium. It's a stratified squamous, but the cells are rounded. They can slide over each other to allow the organ to stretchhhhhh. The cells flatten out when the organ is full. It goes from 6 layers when empty to just three when it is full(perhaps after a drinking binge).

Stratified squamous
Stratified cuboidal
Transitional

Next up,is connective tissue. If epithelial tissue has you covered, connective tissue holds it all together. As its name implies,in connects body parts. The four main functions it has,though, are:

1)binding and supporting
2)protecting
3)insulating
4)transporting substances (in the case of blood)

The four main categories of connective tissue are:

1)connective tissue proper
2)cartilage
3)bone tissue
4)blood

All connective tissues develop from an embryonic tissue called mesenchyme and feature something called an extracelluar matrix, which is the nonliving material found between the cells of the tissue, which give it its strength. All connective tissue has the same three structural elements: ground substance,fibers, and cells.
Ground substance fills the space between cells and contains the fibers. It,in turn, is composed of tissue fluid, cell adhesion proteins(the glue that holds cells to matrix) and proteoglycans(the protein core).The ground substance holds fluids and acts like a sieve which lets nutrients go through between cells and blood capillaries.
Fibers provide support. The three types are:the strong collagen, the rubbery elastic, and the fine reticular.
Cells are a blast. Fibroblast for connective tissue proper, chondroblast for cartilage, osteoblast for bone, and hematopoietic stem for blood.All of these blasted cells make ground substabce and fibers for their matrix.
Connective tissue proper comes in two flavors: loose and dense.
Cartilage is tough and flexible, and has three varieties: hyaline,
elastic, and fibro.

Bone is rocklike and can support and protect like nobody's business.It also provides fat storage and blood cells synthesis.

Blood is the black sheep of the connective tissue family, neither connecting things nor supporting them(boo,hiss). Blood does the transporting for the cardiovascular system, and gets to stay in the family because it develops from the mesenchyme and consists of (blood) cells in a non-living matrix(blood plasma).

(all pics from the JayDoc Histoweb)
http://www.kumc.edu/instruction/medicine/anatomy/histoweb/index.htm

Fetus: not the name of a Roman emporer

2006-02-06T00:16:00.000-08:00

Ladies and gentlemen, it all starts with an embryo...

At one week in the fetal development, all there is are two sheets of cells, also called embryonic germ layers. The ectoderm is the top, the endoderm the bottom. Under the ectoderm, we have the notocord,which is in the middle of the ectoderm, and runs the length of it. A third level called the mesoderm which acts as a "stuffing" layer develops, and above the notocord develops the neural tube. At a point called gastrulation, things start to change. The ectoderm surrounds the endoderm, and two tubes are formed. The outer is known as the somatic, and the inner is the visceral. Between the two we have the celom aka body cavity. The mesentary connects the two tubes, and the mesoderm is found on the inside of both tubes.
Well,what happens from there? From the inner tube aka gut tube develops the lungs, digestive system, liver and pancreas. It ends in the anus, and the gut tube is covered with the lubricated serous lining, or serosa.
From the outer tube aka somatic or parietal, we have skin, skeleton,skeletal muscles and the nervous system. Limbs attach here. The neural tube becomes the spinal cord and attaches to the brain. Even the body cavity aka celom gets into the act, becoming the chest and abdominal regions, otherwise respectively known as the pleural and peritoneal regions, both of which have serous membranes...lubricated,for her pleasure(sorry,couldn't resist).

The Miracle of Life

2006-02-05T23:19:00.000-08:00

How are our amazing bodies organized? Well, there are 6 basic levels:

1.Chemical. Atoms are the tiniest parts of matter, there's nothing smaller! They combine to make molecules (for example, water and proteins). These become organelles, and they in turn, are parts of cells, which leads us to stage two!
2. Cellular. These guys are the smallest units of LIVING things (whereas atoms are the smallest of NON-Living). The study of cells is called microbiology. All cells have similiar functions, but also they have a lot of variation as to size and shape, depending on their separate functions in the body.
3. Tissues. Histology teaches us that groups of cells with similar functions become tissues, of which the four types are: epithelium (covers body and lines cavities), muscle (provides movement), connective (supports organs and protects them), and nervous, which is what this class makes me...no,wait..nervous tissue uses electrical impulses to give us fast internal communication.
4. Organs. If you take at least two types of tissue (but four is more common) and put them together, you get organs. They perform specific functions for the body. The functions get a LOT more complex, at this level. At this point, the study is called anatomy, which deals with the structure of the body. Examples are the stomach, heart, and liver.
5. Organ systems. Organs that work together for a specific purpose are called organ systems. All together, the human body has: digestive, nervous,endocrine, circulatory, respiratory, urinary, reproductive, integumentary, skeletal, muscle, and lymphatic systems. The study of this level is called physiology.
6. Organismal. Put them all togther and, tada! You get the human organism. All structural levels working together result in the miracle of life.

2006-01-23T07:29:00.000-08:00

Stephan Rose
Beverly MA 02-07-1972
Monet
Mom's only child,Dad's 5th
Required for Massage Therapy