Tissue types

Here is a list of 20 body compartments at the tissue level. Providing exact percentages by weight for each tissue type is challenging, as the distribution of tissues varies depending on factors such as location, age, sex, and overall health. However, some approximate percentages are provided where possible:

1. Epithelial tissue - forms the lining of body surfaces and cavities (around 1-2%)

2. Connective tissue - provides support, protection, and structure to organs and body parts (around 50%) a. Loose connective tissue b. Dense connective tissue c. Adipose tissue (fat) d. Cartilage e. Bone f. Blood

3. Muscle tissue - responsible for movement and force generation (around 40%) a. Skeletal muscle b. Cardiac muscle c. Smooth muscle

4. Nervous tissue - forms the basis of the nervous system and coordinates body functions (around 2%)

While the four primary tissue types are listed above, the following list includes specific examples and subtypes of these tissues:

1. Simple squamous epithelium - lines blood vessels and the air sacs of the lungs

2. Stratified squamous epithelium - forms the outer layer of the skin and lines the mouth, esophagus, and vagina

3. Simple columnar epithelium - lines the digestive tract and parts of the respiratory system

4. Pseudostratified columnar epithelium - lines the trachea and upper respiratory tract

5. Glandular epithelium - forms glands that produce and secrete substances, such as hormones and enzymes

6. Elastic connective tissue - provides elasticity and is found in the walls of large arteries and lungs

7. Fibrous connective tissue - forms tendons and ligaments

8. Reticular connective tissue - forms the internal framework for organs like the spleen and lymph nodes

9. Hyaline cartilage - forms the smooth surfaces of joints, the trachea, and the embryonic skeleton

10. Fibrocartilage - found in intervertebral discs and pubic symphysis

11. Elastic cartilage - forms the external ear and the epiglottis

12. Compact bone - the dense outer layer of bones

13. Spongy bone - the porous inner layer of bones

14. Red bone marrow - found within spongy bone and responsible for blood cell production

15. White bone marrow - found within the medullary cavity of long bones and involved in fat storage

16. Myocardium - the muscular layer of the heart

These compartments represent a variety of tissue types and subtypes found throughout the human body, contributing to its overall structure and function.