CD Assignment: Bio 202

Take Home Assignment Number 1 Laayla Muhammad
Due: October 13, 2007


2.4.1 How many layers can you distinguish in the epidermis? The dermis?
Answer: Using the low magnification, I could only distinguish one layer, even though there are five layers in epidermis. I could only distuinguish two layers, when there are actually four layers in the dermis.

2.4.2.1 Now how many layers can you distinguish in each of these tissues?
Using the high magnification, I can distinguish that:
In the Epidermis: The stratum comeum has only one layer, when in actuality, it has up to 30 layers, the stratum lucidum has only one layer, but in actuality it has three to five layers, the stratum granulosum has three layers, when it can range from three to five layers, the stratum spinosum has three layers when it really has many many layers, and the stratum basale has a single layer. I can also distinguish that in the Dermis: The dermal papilla is one layer, which is the superficial tissue; and the reticular is the other layer, which is the deep tissue.

2.4.3 How are the cells in the dermis different from the cells in the epidermis?
The cells in the dermis and the cells in the epidermis are different in variety of ways. First of all, there is more intercellular fluid in each cell of the dermis when compared to the dried up cells in the epidermis. Because of their dryness, the cells in the epidermis tend to look smaller in size. Second of all, the cells in the epidermis are packed closer and are more lined up in an organized manner. The cells in the dermis are not even lined up and tend to swirl together.


3.2 List 3 features of the structure or organization of these two types of bone and tell how they are similar or how they are different in the two types of bone.

As the cancellous bone has spaces between the trabeculae, the compact bone has perforating canals through the osteon. The canal normally pierces oseton at raight angle to central canal. In both, the cancellous bone and the compact bone, nerves and blood vessels travel through channels. When it comes to structure, the cellelous bone is spongy, a feature that cater to its function. The cancellous bone is the inner cavity of the bone, and the compact bone has a central opening with a surrounding cylundrical column of osteon. The compact bone helps support. Both of these bones can also be similar because compact bone contains interstitial lamina and the cancellous bone contain marrow and both of these features fill up spaces between each bone type.


3.4 List 3 features of the structure or organization of these three types of cartilage and tell how they are similar or how they are different in the three types of cartilage.

The three shared features of the structure or organization of the three types of cartilages are lacuna, which are small spaces. These spaces contain chondrocytes, which arespread through the matrix. This feature is in all three of the cartilages. Fibrous cartilage lacks a certain layer, that Elastic and Hyaline cartilages have, which is a chondrogenic layer of the perichondrium. All three of these cartilages differ in their functions of the matrix formations. The fibrous cartilage contains bundles of branding elastic fibers and chondrocytes which are arranged in clusters through the matrix. It has an alternating layering of hyaline and collagen fibers becaue the elastic cartilage only has bundles of branching elastic fibers while the hyaline cartilage has chondrocytes in custers.

4.2 List 3 features of the structure or organization of these three types of muscle and tell how they are similar or how they are different in the three types of muscle tissue.

The three features of the structure or organization of the three types of muscle (smooth, cardiac, and skeletal) differ and relate to each other in variety of ways. The smooth muscle
The smooth muscle (involuntary) has spindle-shaped muscle cells with tapered ends and have single oval shaped nucleus. Fibers are tightly packed and arranged in staggered arrays. Skeletal muscle has an elongated nucleus that are outside of the cell. There are dark and light unique transverse bands inside. Cardiac muscle has some features of skeletal muscle and some features of smooth muscle, making it a combination of both. In cardiac muscles, cells branch and join to each other by intercalated discs that can be distinguished by microscopes. Cardiac muscle and skeletal muscle are similar because they have narrow transverse bands and multiple nucleus. Cardiac and smooth muscles are similar since nuclei are elongated.