The Human Body: An Orientation

Question 1

What is the difference b/w Histology and Radiography?

Answer 1

1. Histology: (aka. microscopic anatomy)
   - The study of structures that are so small they can be seen only w/ a microscope.
   - These structures include cells and cell parts
2. Radiography
   - The study of internal body structures by means of X-ray studies and other imaging techniques.

Question 2

Define a tissue.

List the 4 types of tissue in the body and briefly state the function of each

Answer 2

1. Tissue - a group of cells that work together to perform a common function
2. 4 types of tissues:
   a. Epithelial tissue - covers the body surface and lines its cavities
   b. Connective tissue - supports the body and protects its organs
   c. Muscle tissue - provides movement
   d. Nervous tissue - provides fast internal communication by transmitting electrical impulses

Question 3

List the Organ systems and their major functions

Answer 3

1. Integumentary sys
2. Skeletal sys
3. Muscular sys
4. Nervous sys
5. Endocrine sys
6. Cardiovascular sys
7. Lymphatic sys / Immunity
8. Respiratory sys
9. Digestive sys
10. Urinary sys
11. Reproductive sys (male & female)

Question 4

Function of the Integumentary sys

Answer 4

• Forms the external body covering and protects deeper tissues from injury
• Synthesizes vit D and houses cutaneous receptors (pain, pressure, etc) and sweat and oil glands

Question 5

Function of the Skeletal sys

Answer 5

• Protects and supports body organs and provides a framework the muscles use to cause movement
• Blood cells are formed w/i bones. Bones store minerals

Question 6

Function of the Muscular sys

Answer 6

• Allows manipulation of the environment, locomotion and facial expression
• Maintains posture and produces heat

Question 7

Function of the Nervous sys

Answer 7

As the fast-acting control sys of the body, it responds to internal and external changes by activating appropriate muscles and glands

Question 8

Function of the Endocrine sys

Answer 8

Glands secrete hormones that regulate processes such as growth, reproduction, and nutrient use (metabolism) by body cells

Question 9

Function of the Cardiovascular sys

Answer 9

• Blood vessels transport blood, which carries O2, CO2, nutrients and wastes, etc
• The heart pumps blood

Question 10

Function of the Lymphatic sys/ Immunity

Answer 10

• Picks up fluid leaked from blood vessels and returns it to blood
• Disposes of debris in the lymphatic stream
• Houses white blood cells (lymphocytes) involved in immunity
• The immune response mounts the attach against foreign substances w/i the body

Question 11

Function of the Respiratory sys

Answer 11

• Keeps blood constantly supplied w/ O2 and removes CO2

- The gaseous exchanges occur thr. the walls of the air sacs of the lungs

Question 12

Function of the Digestive sys

Answer 12

• Breaks down food into absorbable units that enter the blood for distribution to body cells
• Indigestible foodstuffs are eliminated as feces

Question 13

Function of the Urinary sys

Answer 13

• Eliminates nitrogenous wastes from the body

- Regulates water, electrolytes, and acid-base balance of the blood

Question 14

Function of the Reproductive sys

Answer 14

• Overall function is production of offspring
• Testes produce sperm and male sex hormone, and male ducts and glands aid in delivery of sperm to the female reproductive tract
• Ovaries produce eggs and female sex hormones
• The remaining female structures serve as sites for fertilization and development of the fetus
• Mammary glands of female breasts produce milk to nourish the newborn

Question 15

List the Axial regions

Answer 15

1. Cephalic
2. Cervical
3. Thoracic
4. Abdominal
5. Pelvic (thorax, abdomen and pelvis are grouped into trunk)
6. Pubic (genital)
7. Perineal (also belongs to trunk)

Question 16

List the appendicular regions

Answer 16

Appendages are also called extremities

1. Upper limb
2. Manus (hand)
3. Lower limb
4. Pedal (foot)

Question 17

List the 3 planes

Answer 17

1. Frontal (coronal) Plane - extends vertically and divides the body into anterior and posterior parts
2. Transverse (horizontal) Plane - runs horizontally from right to left, dividing the body into superior and inferior parts
3. Median (midsagittal) plane - vertical, divide the body into right and left parts (lies in the midline)
   - - If the sagittal plane doesn’t lie in the midline, it’s parasagittal plane.

Question 18

List the basics features that vertebrates share

Answer 18

1. Tube-w/i-a-tube body plan
2. Bilateral symmetry
3. Dorsal hollow nerve cord
4. Notochord and vertebrae
5. Segmentation
6. Pharyngeal pouches

Question 19

Dorsal body cavity: subdivisions

Answer 19

Subdivided into a cranial cavity and vertebral cavity

1. Cranial cavity: lies in the skull and encases the brain
2. Vertebral cavity: runs thr. the vertebral column to enclose the spinal cord

Question 20

Ventral body cavity: subdivisions

Answer 20

Divided into 2 main parts:

1. Superior thoracic cavity: surrounded by the ribs and the muscles of the chest wall
2. Inferior abdominopelvic cavity: surrounded by the abdominal walls and pelvic girdle

Note: the two divisions are separated by the diaphragm

Question 21

List the parts in the Thoracic cavity, and the organs enclosed

Answer 21

1. Pleural cavity (two lateral parts) – Lungs
2. Mediastinum
   a. Superior mediastinum - housing other major thoracic organs, such as the esophagus and trachea
3. Pericardial cavity within the mediastinum - Heart

Question 22

List the parts in the Abdominopelvic cavity, and the organs enclosed

Answer 22

The cavity is surrounded by a peritoneal cavity; the two parts below are not separated but continuous

1. Abdominal cavity (superior part)
   - Liver, stomach, kidneys and other organs
2. Pelvic cavity (inferior part)
   - bladder, some reproductive organs and the rectum

Question 23

List the 3 serous cavities and Name the two serous membranes that line the serous cavity

Answer 23

1. Serous cavities:
   - Pleura
   - Pericardium
   - Peritoneum
2. Membranes
   - Parietal serosa
   - Visceral serosa
   - Serous cavity (in b/w the two membrane) - filled with serous fluid produced by BOTH membranes

Question 24

Orientation and Directional Terms and know their meanings

Answer 24

1. Superior (cranial) / Inferior (caudal)
2. Medial / Lateral
3. Proximal / Distal
4. Ipsilateral / Contralateral
5. Anterior (ventral) / Posterior (dorsal)
6. Superficial (external) / Deep (internal)

Question 25

The 2 commonly used histological stains for LM

Answer 25

1. Hematoxylin & Eosin (H&E stain) - Hematoxylin is basic stain - will bind to acidic structures Ex. nucleus, ribosomes, rough ER - Stain purple / blue - Eosin is acidic stain - will bine to basic structures Ex. basic cytoplasmic structures and extracellular components. - Stain red / pink

Question 26

How are tissues stained for TEM

Answer 26

Heavy-metal salts - deflect electrons in the beam to different extents, providing contrast in the image

Question 27

Scanning Electron Microscopy

Answer 27

1. Used to provide 3D pictures of whole, unsectioned surfaces w/ striking clarity 2. Procedures - Specimen is preserved and coated w/ fine layers of carbon and gold dust - Scan the specimen w/ an electron beam, which cause the secondary electrons to be emitted from its surface - A detector captures these emitted electrons and assembles them into a 3D image on a video screen

Question 28

X ray image

Answer 28

Absorption of X-ray depends on the density of the matter encountered, such as bones, tumors, TB nodules - Darker area (exposed areas): represents soft organs which are easily penetrated by X-rays - Light area (unexposed areas): corresponds to denser structures, such as bones, which absorb most X-rays Hollow soft tissue: enhanced by contrast medium, such as barium (absorb more X-rays) -- screen for ulcers and tumors

Question 29

CT scanning

Answer 29

CT = computed tomography: produce superb images of soft tissue as well as of bone and blood vessels -- Providing good info in trauma situation to assess internal injury 1. Patients lies in the central hole, situated b/w an X-ray tube and a recorder. The tube and the recorder rotate to make ~12 successive X-ray images around the person's full circumference. 2. Pictures are axial images (transversal)

Question 30

Angiography

Answer 30

Angiography: a technique that produces image of blood vessels - A Contrast medium is injected into a vessel and distributed via the vascular system. - Used to diagnose aneurisms and atherosclerosis and for identifying a source of internal bleeding

Question 31

DSA (digital subtraction angiography)

Answer 31

- Images of the vessel are taken before and after the injection of contrast medium - The computer subtracts the "before" from the "after" image - Used to identify blockage of the arteries that supply the heart wall and the brain

Question 32

PET scan

Answer 32

PET = positron emission tomography 1. Produce images by detecting radioactive isotopes injected into the body - 2. Used to assess the functional flow of blood and areas of high metabolic activity, such as tumors b4 they are visible in CT or MRI imaging. - Used to monitor the size and distribution of tumors and the response of cancerous tumors to therapeutic treatments -- As the radioactive material decays, it gives off energy in the form of gamma rays. Sensors pick the gamma rays, which are translated into electrical impulses and sent to the computer

Question 33

MRI

Answer 33

MRI = Magnetic resonance imaging 1. Detects the levels of the element hydrogen in the body, most of which is water. -- distinguish body tissues from one another on the basis of differences in water content - Bones contain less water than other tissues - Fatty white matter contain less water than gray matter of the brain - Joints, ligaments, cartilages are also visualized w/ MRI Mechanisms: 1. During the MRI scan, the nuclei of the body's (spinning) H atoms line up patrolled to the strong magnetic field. The patient is then exposed to a brief pulse of radio waves which knock the spinning protons. 2. When the radio waves are turned off, the protons return to their alignment in the magnetic field, emitting their own faint radio waves in the process

Question 34

Sonograph

Answer 34

1. aka. ultrasound 2. Provides sonar images of developing fetuses and internal body structures. 3. Allows for immediate, inexpensive visualization of internal organs