Human Anatomy and Physiology 1 HOMEWORK 7
Complete each sentence by dragging the proper word or phrase into the correct position.
- Skin contains the protein keratin and cellular junctions called desmosomes that confer a mechanical strength to the epidermis, which RESISTS MECHANICAL TRAUMAS such as punctures and abrasions. - As a result of impermeable cellular junctions and water-proofing lipids, the epidermis functions in CREATING A BARRIER TO SOME FLUIDS . - The skin assists endocrine function by playing a role in VITAMIN D SYNTHESIS, which is needed for calcium homestasis.
Complete each sentence by dragging the proper word or phrase into the correct position. Then place the sentences in order from superficial to deep.
1. The STRATUM CORNEUM is made up of multiple layers of dead keratinocytes that regularly exfoliate. 2. The next layer is the STRATUM LUCIDUM which is present only on the soles of the feet, hands, fingers, and toes. 3. The STRATUM GRANULOSUM is named for the presence of dark staining keratohyalin granules which bind the cytoskeletal keratin filaments together. 4. Towards the apical surface, in the STRATUM SPINOSUM, the keratinocytes cease cell division, while at the deeper regions they can still undergo mitosis. 5. Comprised of viable, cuboidal and columnar cells, the STRATUM BASALE contains the keratinocyte stem cells that replenish the exfoliated cells at the surface.
Complete each sentence regarding skeletal function by dragging the proper word or phrase into the appropriate position.
1. The bones of the skeleton provide structure to the body and serve as a SUPPORT to hold up the body and maintain proper positioning of some organs. 2. The skull, pelvis, ribs, vertebral column, and sternum provide PROTECTION to many delicate organs of the body by encasing them in hardened, shell-like or caged structures. 3. The MOVEMENT of the entire skeleton or skeletal elements utilizes the anchoring of muscles to attachment sites on the bones, which then serve as levers. 4. Minerals can be stored in the skeleton, which acts as a reservoir, storing or releasing minerals as needed to maintain ELECTROLYTE BALANCE throughout the body. 5. The storage or release of buffering compounds works to aid the body in ACID BASE balance. 6. Contained within the spongy sections of bones, red bone marrow is responsible for BLOOD FROMATION .
Identify the following layers of the epidermis from the descriptions. 2-12-2013
1. The statrum BASALE is a single layer of columnar or high cuboidal cells resting on a basement membrane. 2. The stratum SPINOUSM is composed of many layers of keratinocytes that are firmly attached to each other by desmosomes. This layer also contains dendritic cells. 3. The stratum GRANULOSUM is composed of 3-5 layers of flattened keratinocytes containing dark staining keratohyalin granules. 4. The stratum LUCIDUM is a translucent layer composed of 3-5 layers of keratinocytes without nuclei or organelles. 5. The stratum CORNEUM is composed of up to 30 layers of cornified, dead cells.
Drag each label into the proper position to identify the type of bone described.
COMPACT BONE - made up of osteons - also called dense bone - visible, obvious, central canals - found in greater proportion in the bone diaphyses SPONGY BONE - composed of trabeculae - convey strength with lightweight - found in greater proportions in flat bones - gaps between ossified material are filled with marrow - arranged along the lines of forces that are encountered - found in greater portions in bone epiphyses
Drag each label into the proper position identifying to which portion of the bone matrix it pertains.
ORGANIC - collagen - glycosaminoglycans - proteoglycans - glycoproteins - provides flexibility - resists tensile (pulling) forces INORGANIC - resists compressive - provides hardness - hydroxyapatite - calcium carbonate
Drag each label into the proper position to identify the type of bone cell described.
Osteogenic Cells - stem cells - differentiate into osteoblasts Osteocytes - bone cells encased in matrix - trapped in lacunae Osteoclasts - bone-resorbing cells - have a ruffled border - massive multinucleate cells Osteoblasts - bone-building cells - abundant in mitochondria - overactivity results in increased bone density
Place the following stages into the correct spaces to represent the chronological order of intramembranous ossification.
Stage 1 - Deposition of osteoid tissue into embryonic mesenchyme Stage 2 - Calcification of osteoid tissue and entrapment of osteocytes Stage 3 - Honeycomb of spongy bone with developing periosteum Stage 4 - Filling of space to form compact bone at surfaces, leaving spongy bone in middle
Mineralization is a process that extracts __________ and __________ from the blood plasma and deposits it into bone.
calcium; phosphate
If the __________ component of bone is not in adequate amounts, the flexibility of bone will be compromised.
collagen
Bone dissolving cells on bone surfaces are called __________.
osteoclasts
The __________ contains hydrogen pumps that lead to the formation of hydrochloric acid, which is used to dissolve bone minerals in a process called __________.
osteoclasts; mineral resorption
