Chapter 4

The _______ is the smallest unit of life.

Every cell is descended from another cell. This idea is part of _______ a. evolution b. the theory of heredity c. the cell theory d. cell biology

True or false? Some protists have no nucleus.

Cell membranes consist mainly of a _______ a. carbohydrate bilayer and proteins b. protein bilayer and phospholipids c. lipid bilayer and proteins

Unlike eukaryotic cells, bacterial cells _______ a. have no plasma membrane b. have RNA but not DNA c. have no nucleus d. a and c

In a lipid bilayer, _______ of all the lipid molecules are sandwiched between all the _______ a. hydrophilic tails; hydrophobic heads b. hydrophilic heads; hydrophilic tails c. hydrophobic tails; hydrophilic heads d. hydrophobic heads; hydrophilic tails

Enzymes contained in _______ break down worn-out organelles, bacteria, and other particles.

Put the following structures in order according to the pathway of a secreted protein: a. plasma membrane b. Golgi bodies c. endoplasmic reticulum d. post-Golgi vesicles

The main function of the endomembrane system is building and modifying _______ and _______ .

Is this statement true or false? The plasma membrane is the outermost component of all cells. Explain.

No animal cell has a a. plasma membrane b. flagellum c. lysosome d. cell wall

_______ connect the cytoplasm of plant cells. a. Plasmodesmata b. Adhering junctions c. Tight junctions d. a and b

Match each cell component with its function. $$ \text {mitochondrion} \quad \quad\quad\quad\quad \text {a. protein synthesis } $$ $$ \text {chloroplast} \quad \quad\quad\quad\quad \text {b. associates with ribosomes} $$ $$ \text {ribosome} \quad \quad\quad\quad\quad \text {c. ATP production} $$ $$ \text {smooth ER} \quad \quad\quad\quad\quad \text {d. sorts and ships} $$ $$ \text { Golgi body} \quad \quad\quad\quad\quad \text {e. assembles lipids botamen} $$ $$ \text {rough ER} \quad \quad\quad\quad\quad \text {f. photosynthesis} $$