Assignment 1 – (50 marks)
Discuss the importance of body fluids and which one is considered to be the body’s internal environment. (4 marks)
* Body fluids carry chemical communicators which organize actions amid cells, carry nutrients to cells, and carry waste products away from cells. They are the primary transport system between cells. The internal environment of the body is extracellular fluid, which refers to all of the fluids outside of our cells in our bodies – such as blood plasma, interstitial fluid, lymph and transcellular fluid. These fluids make up approximately 1/4 of body weight.
Describe the three major types of lipids found in the body. (6 marks)
* The three major ...view middle of the document...
Some may also have cilia to aid moving materials over surfaces. Transitional cells can be tall or flat, and can compress or extend to respond to body movement.
Describe the structural characteristics of the epidermis that relate to its protection function. Compare thick to thin skin. (6 marks)
Tight junctions work towards preventing bacterial invasion in epithelial cells, as well as keratin, which is a thick protective layer of the epidermis. Not only does keratin protect from bacterial invasion, but also blocks UV damage. The dermis is thinner in thick skin compared to thin. Thick skin also doesn’t have hairs, apocrine sweat glands, or sebaceous glands. It’s commonly found where there’s lots of abrasion. For example, palms, fingertips and soles of feet. In contrast, the dermis is thicker in thin skin than it is in thick. This makes thin skin easier to suture if injury is acquired. As well, thin skin has less eccrine sweat glands than thick skin.
Briefly describe the steps in endochondral ossification. (6 marks)
* Firstly, in the center of hyaline cartilage, chondrocytes expand and form struts. These start to calcify, and the expanded chondrocytes die. This leaves cavities in the cartilage. Secondly, blood vessels grow around the cartilage. This is where osteoblasts are formed from cells in the perichondrium, which produce superficial bone around the shaft. This continues to grow and eventually turns into compact bone. This is referred to as appositional growth. Thirdly, blood vessels go into the cartilage carrying osteoblasts. At the primary ossification center, spongy bone develops. Fourthly, a marrow cavity is created. At the metaphysis, bone replaces cartilage. Fifthly, secondary ossification centers are created by the osteoblasts and capillaries entering the epiphyses. Lastly, spongy bone fills the epiphyses, and the remaining cartilage in the joint cavity is the articulation cartilage.
Choose the answer from the left column that best matches the description or term in the right column. (5 marks)
facetsfissuresforaminacondylescrestsnasal bonesossiclestemporal bonesvomerzygomatic bonescervical vertebraecoccyxlumbar vertebraesacral vertebraethoracic vertebrafalse ribsfloating ribsmanubriumtrue ribsxiphoid process | along with thoracic vertebrae, make up primary curvature of spinelandmark for CPRprominent ridge found on sacrumsmallest bones in bodyattach directly to sternummany found in skull; allow passage of nerves and blood vesselsusually 5 of these, largest bodies, short rectangular spinous processessuperior portion of sternumtwo found on atlas, articulate with occipital condylesforms inferior portion of bony nasal septum |
Compare the pectoral and pelvic girdles. (4 marks)
* In comparison of size, the pectoral girdle is much bigger than the lighter pelvic girdle. The pectoral girdle also has a more shallow socket, while the pelvic girdle has deeper, more ensured sockets for limb attachment. As well,...