Question

cell diversity
so far in this chapter, we have focused on a generalized human cell. however, the trillions of cells in the human body include over 200 different cell types that vary greatly in size, shape, and function. they include sphere - shaped fat cells, disc - shaped red blood cells, branching nerve cells, and cube - shaped cells of (1. ) tubules. depending on type, cells also vary greatly in length—ranging from 1/12,000 of an inch in the smallest cells to over a yard in the nerve cells that cause you to wiggle your toes. a cells shape reflects its function. for example, the flat, tile - like epithelial cells that line the inside of your cheek fit closely together, forming a living (2. ) that protects underlying tissues from bacterial invasion. the shapes of cells and the relative numbers of the various organelles they contain relate to specialized cell functions (figure 3.8). lets take a look at some examples of specialized cells. cells that connect body parts (figure 3.8a) fibroblast: this cell has an elongated shape, like the cable - like fibers that it secretes. it has an abundant rough er and a large golgi apparatus to make and (3. ) the protein building blocks of these fibers. erythrocyte (red blood cell): this cell carries oxygen in the blood. its biconcave disc shape provides extra surface area for the uptake of oxygen and streamlines the cell so it flows easily through the bloodstream. so much oxygen - carrying pigment is packed in erythrocytes that all other (4. ) have been shed to make room. cells that cover and line body organs (figure 3.8b) *epithelial cell: the hexagonal shape of this cell is exactly like a cell in a honeycomb of a beehive. this shape allows epithelial cells to pack together in sheets. an epithelial cell has abundant intermediate filaments and desmosomes that resist tearing when the (5. ) is rubbed or pulled.

1. kidney 2. barrier 3. secrete 4. organelles 5. epithelium

1. secrete 2. organelles 3. epithelium 4. kidney 5. barrier

1. barrier 2. secrete 3. organelles 4. epithelium 5. kidney

1. organelles 2. epithelium 3. kidney 4. barrier 5. secrete

1. epithelium 2. kidney 3. barrier 4. secrete 5. organelles

Explanation:

1. Cub - shaped cells are found in kidney tubules.
2. Flat, tile - like epithelial cells form a living barrier to protect underlying tissues.
3. Fibroblasts make and secrete the protein building blocks of fibers.
4. Erythrocytes have shed other organelles to make room for oxygen - carrying pigment.
5. Epithelial cells with abundant intermediate filaments and desmosomes resist tearing when the epithelium is rubbed or pulled.

Answer:

1. kidney
2. barrier
3. secrete
4. organelles
5. epithelium