Biology Ch.6 (a)

5 Written Questions

1. surface lacks ribosomes
2. focuses a beam of electrons through the specimen or onto its surface.
3. an electron beam scans the surface of the sample. The beam excites electrons on the surface and these secondary electrons are detected. The result is the image
4. encloses the nucleus, separating its contents from the cytoplasm.
5. carries out a variety of tasks in the cell such as synthesis of proteins and their transport into membranes and organelles or out of the cell.

5 Matching Questions

1. prokaryotic cell
2. phagocytosis
3. nucleolus
4. cystol
5. transmission electron microscope

1. a the DNA is concentrated in the nucleoid
2. b a prominent structure within the nondividing nucleus which appears through the electron microscope as a mass of densely stained granules of fibers adjoining part of the chromatin.
3. c a semi fluid, jellylike substance
4. d used to study the internal ultra structure of cells.
5. e eat by engulfing smaller organisms or other food particles

5 Multiple Choice Questions

1. a netlike array of protein filaments that maintains the shape of the nucleus by mechanically supporting the nuclear envelope
   1. nuclear envelope
   2. nuclear lamina
   3. nucleolus
   4. nucleoid
2. surface has ribosomes
   1. smooth er
   2. rough er
   3. ribosomes
   4. vesicles
3. - the boundary of every cell. Functions as the selective barrier that allows sufficient passage of oxygen, nutrients, and wastes to service the entire cell
   1. smooth er
   2. rough er
   3. plasma membrane
   4. nuclear lamina
4. membrane-enclosed compartments
   1. ribosomes
   2. vesicles
   3. organelles
   4. nucleolus
5. the interior of a prokaryote cell
   1. cytoplasm
   2. vesicles
   3. chromatin
   4. cystol

5 True/False Questions

1. central vacuole → pump excess water out of the cell, thereby maintaining a suitable concentration of ions and molecules inside the cell

   True        False

2. glycoproteins → proteins that have carbohydrates covalently bonded to them

   True        False

3. eukaryotic cell → the DNA is concentrated in the nucleoid

   True        False

4. food vacuoles → develops by the coalescence of smaller vacuoles themselves derived from the GA and ER.

   True        False

5. endoplasmic reticulum → consists of a network of membranous tubules and called cisternae. Site for protein synthesis.

   True        False