Cell Division

Cell division begins with Interphase. It's about 1/3 of the time required for cell division. It contains the G1, S, and G2 phases. Some nerve cells have a Go phase. Chromosomes are duplicated.

Somatic cell division is cytoplasmic division [cytokinesis] and nuclear division [mitosis]. The stages of mitosis are prophase, metaphase, anaphase, and telophase. Interphase occurs between cell divisions and is when organelles and DNA are duplicated.

During prophase, the threats off chromatin become tightly coiled and condense into chromasomes, the little X's that contain all coiled up DNA. A chromosome is made of two strands, or chromatids, and are held at the center by a round centromere. A protein structure called a kinetochore surrounds the centromere and the chromatid spindles bond to it.

Centrioles are those rodlike bundles that go around the nucleus to divide it eventually. They have microtubules to help accomplish this, called asters. The nuclear membranes disperse into the cytoplasm and the nucleoli break down and disappear.

In metaphase, the nuclear membrane has broken down and the spindle fibers have moved into the nuclear area. The chromosomes line up along the plane midway between the poles, forming the metaphase, or equatorial, plane. Two chromatids of each chromosome seperate. Formation of the metaphase plane and duplication of the centromeres completes metaphase.

In anaphase, the shortest of the mitotic phases, the centromeres divide so that each chromatid has its own. Anaphase is characterized by the migration of the chromatids. The two chromatids of each chromosome move toward opposing poles, with the centromeres leading the way. The contractile proteins of the spindles are responsible for pulling the chromatids toward each centriole.

In telophase the chromosomes uncoil and return to DNA strands in the 2 new nuclear membranes. Spindle fibers disappear into the cytoplasm nucleoli reappear in the nuclei. the cytoplasm divides [cytokinesis] with its organells, and two identical cells with identical DNA are left.

Organs

The heart is protected by the pericardium, which is a double walled membrane around the heart.

to be continued

Terms

Studying structure is anatomy. Studying function is physiology. Something can have numerous physiological purposes.

A cell is made of a nucleus and cytoplasm, made of a watery matrix cytosol, and organelles. Cells comine to form a tissue. All tissues are epithelium, connective, muscle, or nerve. Tissues grouped to perform a function form organs. An organ system is a serious of organs together. The human body has 10 organ systems. Together they form an organism. A series of humans connected electromagnetically by their language centers and other portions of the brain and body circuitry form the human organism.

Superior is to the upper end of the body in the same plane. Inferior means below. Ventral or anterior refers to the front of the body. The Anterior portion of the Caribbean is the 'front' to European powers. Antilles? It may not be technically a fact but i will remember it that way.

Posterior or dorsal refer to the backside. Medial is the middle. Lateral is to the side. Proximal is of proximity to the center. A proximal item to closer to the source. A distal item is more distant from the source.

Ipsilateral is the same side of the body. Contralateral is different sides of the body.

Superficial vs deep.

Planes: sagittal. From superior to inferior. Vertical. Mid-sagittal means equal on both sides. Parasagittal is not equal on both sides. Transverse is horizontal. Frontal or coronal is into dorsal and ventral portions. Oblique is odd cuts.


Armpit is axillary. Arm is brachial. Front of elbow is antecubital. The cubit is from the elbow to the tip of the finger. About 18". Before the cubit is the elbow. The back of the elbow is olecranal. The forearm is literally antebrachial. The wrist is a carpal. The hand is metacarpal. After the wrist. Palm of hand is palmar or volar. The thumb is a pollex! Fingers are phalangial. Phalanxes from the hand. German: catchers. The thigh is femoral. The femoral artery can be used in the heart and is located in the thigh. The front of the knee is patellar. The back of the knee is popliteal. That'd suck. The leg is crural. Probably more specifically referred to in actuality, but crural nonetheless. The foot is pedal. Ankle is tarsal. The tarsus. The top of the foot is the dorsum. Dorsal is the back portion... of the foot. The top. The 'great toe' is the hallux. Like pollex of the foot. Toes are phalangeal to the foot. The groin is inguinal.

The head is cephalic. Cephalitis = pride. The skull is cranial. Frontal = forehead. Above eyes = superio-orbital. The eye is an orbit. The ear is otic, like the otic nerve. The cheek is buccal. The chin is mental, like the thinker. The neck is cervical, like an opening. If you cut a head off there is a hole there called the neck. The nape of the neck is nuchal, which is just fine. The chest is thoracic like the thorax of an insect. The naval is umbillical. The hip is coxal.

The shoulders are acromial. Acrobatics involve shoulder use. The upper back is the scapular. The lower back is the lumbar. There are actually 5 regions of the spine involving the acronym CTLSC. The buttocks are gluteal. the calf is sural. Between the hips is also sacral. Hence the sacroiliac. The sole of the foot is plantar, where plantars warts go. The heel of the foot is calcaneal.

The body cavities: Dorsal Cavities. Cranial cavity in the skull. The vertebral cavity is the spinal column for that fluid and bone.

The Ventral Cavities: The Thoracic Cavity and the Abdominopelvic Cavity are in the ventral aspect of the body. They are seperated by the diaphraghm.

Inside the Thoracic Cavity is the Mediastinal Cavity, holding the heart, between the stinal areas, Pleural Cavities. Lungs are pleural. Pleurisy. The right lung has 3 lobes. The left lung has two and has the cardiac notch where the heart fits.

Organ Systems 1

The integumentary system is the integrity of the body. It is the skin, largest organ. Hair and nails are also fluff on the skin. Sweat glands and sebaceous glands which make oil. It protects organs, keeps out microorganisms, synthesized vitamin D, regulates body temperature and humidity.

The skeletal system contains 206 bones, cartilidge of various types, ligaments, which connect bones together, tendons, which connect muscles to bones. Skeleton protects internal organs and produces the majority of motion. Tendons must be spiral-coiled items like 3 twine stretchy ropes.

The muscular system contains skeletal muscles, attached to bone and for voluntary movement. It has smooth muscles for involuntary movement. And cardiac muscle for the heartbeat. 3 special kinds of muscle.

The nervous system has the cns -brain and cord, and pns, nerves. PNS also includes cranial nerves which supply the head, neck, face, and shoulder area, although there is one cranial nerve that supplies all our internal organs. PNS: autonomic nerves for body control breathing, temperature. Special sense organs ears eyes taste, touch smell.

The endocrine system contains ductless glands. recall that exocrine glands have a duct while endocrine systems drop it outside. The pineal, thymus, thyroid, parathyroid, adrenal, pancrease, and sex bunches.

The cardiovascular system contains the hear, arteries and veins, blood, and capillaries.

The lymphatic system contains the lymph nodes, lymphatic vesselrs, lymph, and thymus gland, and tonsils. The purpose of this system is to drain all vital nutrients from the fluids surrounding our cells and return those to the circulating blood.

The respiratory ststem has the nasal cavities, the pharynx [throat] the trachea and its subdivisions, the lungs, the respiratory diaphraghm. Divisions in the trachea are called bronchi.

The digestive system contains the oral cavity, the pharynx, the esophagus, the stomach, the small and large intesines.

The urinary systems contains the kidneys, the ureters, the bladder, and urethra. You make like 1ml of urine every minute or so.

The reproductive system contains your sexy bits. even the epididymus and bulbourethral glands.

The NONOGRAPH:

umbillical region in center. right and left hypochondriac regions. 'hypo: below chondriac:the cartilidge'. epigastric is above the stomach, and between the two hypochondriac regions. two midlateral regions: right and left lumbar regions. correspond to the lumbar region of the back. r& l inferiolateral regions. hypogastric region.