CHAPTER 1 A&P
🟣 Directional Terms
1. Anatomical position — Standing upright, facing forward, arms at sides, palms facing forward, feet forward.
Example: All directional terms assume this position.
2. Superior (cranial) — Toward the head/above.
Example: The chest is superior to the abdomen.
3. Inferior (caudal) — Toward the feet/below.
Example: The stomach is inferior to the heart.
4. Anterior (ventral) — Toward the front of the body.
Example: The sternum is anterior to the heart.
5. Posterior (dorsal) — Toward the back of the body.
Example: The spine is posterior to the heart.
6. Medial — Toward the body's midline.
Example: The nose is medial to the eyes.
7. Lateral — Away from the body's midline.
Example: The ears are lateral to the eyes.
8. Intermediate — Between a more medial and more lateral structure.
Example: The clavicle is intermediate between the sternum and shoulder.
9. Proximal — Closer to the point of attachment/origin.
Example: The elbow is proximal to the wrist.
10. Distal — Farther from the point of attachment/origin.
Example: The fingers are distal to the elbow.
11. Superficial — Toward/at the body's surface.
Example: The skin is superficial to the muscles.
12. Deep — Farther from the body's surface.
Example: The bones are deep to the muscles.
13. Ipsilateral — On the same side of the body.
Example: Right arm + right leg = ipsilateral.
14. Contralateral — On opposite sides of the body.
Example: Right arm + left leg = contralateral.
🔵 Body Planes
15. Sagittal plane — Divides the body into left and right portions.
16. Midsagittal (median) plane — Divides the body into EQUAL left and right halves.
17. Parasagittal plane — Divides into UNEQUAL left and right portions.
18. Frontal (coronal) plane — Divides the body into anterior/front and posterior/back portions.
19. Transverse (horizontal) plane — Divides the body into superior/top and inferior/bottom portions.
20. Oblique plane — Cuts the body at an angle.
🧠 Memory trick:
Sagittal = Sides (L/R)
Frontal = Front/back
Transverse = Top/bottom
🟢 Body Cavities
21. Body cavity — Internal space that houses and protects organs.
22. Dorsal body cavity — Cavity along the back/posterior body; contains the brain and spinal cord.
23. Cranial cavity — Contains and protects the brain.
24. Vertebral (spinal) cavity — Contains and protects the spinal cord.
25. Ventral body cavity — Large anterior cavity containing many internal organs.
26. Thoracic cavity — Chest cavity superior to the diaphragm; contains heart and lungs.
27. Pleural cavities — Cavities surrounding the lungs. Each lung has its own pleural cavity.
28. Mediastinum — Central region between the lungs; contains the heart, trachea, esophagus, etc.
29. Pericardial cavity — Cavity surrounding the heart, located within the mediastinum.
30. Abdominopelvic cavity — Ventral cavity inferior to the diaphragm; includes abdominal + pelvic cavities.
31. Abdominal cavity — Contains organs such as the stomach, liver, spleen, kidneys and most intestines.
32. Pelvic cavity — Contains structures such as the urinary bladder, reproductive organs and rectum.
33. Diaphragm — Muscle separating the thoracic cavity from the abdominopelvic cavity.
🧠 Think hierarchy:
Dorsal → Cranial + Spinal
Ventral → Thoracic + Abdominopelvic
Thoracic → Pleural + Mediastinum → Pericardial
Abdominopelvic → Abdominal + Pelvic
🩷 Histology Foundations
34. Histology — Study of tissues under a microscope.
35. Tissue — Group of similar cells working together for a particular function.
36. Four primary tissue types — Epithelial, connective, muscle, nervous.
37. Epithelial tissue — Covers body surfaces, lines cavities/organs and forms glands. Cells are usually tightly packed.
38. Connective tissue — Supports, binds, protects and connects structures. Usually has lots of extracellular matrix.
39. Muscle tissue — Specialized to contract and create movement.
40. Nervous tissue — Specialized for communication through electrical signals; found mainly in brain, spinal cord and nerves.
🟡 Epithelial Tissue — SUPER IMPORTANT
41. Simple epithelium — ONE layer of cells.
🧠 Simple = single.
42. Stratified epithelium — MULTIPLE layers of cells.
🧠 Stratified = stacked.
43. Squamous cells — Flat and thin cells.
🧠 Think: squished.
44. Cuboidal cells — Roughly cube-shaped; height ≈ width.
45. Columnar cells — Tall, rectangular cells.
🧠 Think: columns.
46. Simple squamous epithelium — One layer of flat cells; good for rapid diffusion/filtration.
Example: Alveoli of lungs and lining of blood vessels.
47. Simple cuboidal epithelium — One layer of cube-shaped cells; secretion and absorption.
Example: Kidney tubules.
48. Simple columnar epithelium — One layer of tall cells; absorption and secretion.
Example: Digestive tract.
49. Stratified squamous epithelium — Many layers; surface cells are flat. Protects against abrasion.
Example: Skin and lining of mouth/esophagus.
50. Pseudostratified columnar epithelium — Looks multilayered because nuclei sit at different heights, but EVERY cell touches the basement membrane.
Example: Much of the respiratory tract.
🔥 Picture-recognition rule
When they give you a histology image, ask yourself in THIS order:
How many layers? → ONE = simple / MANY = stratified.
Then: What shape are the cells at the FREE/APICAL surface? → flat = squamous / cube = cuboidal / tall = columnar.
