Chapter 4 Review

​ (a)   ​ is the ratio of microscopic size to actual size of an object, and​ (b)   is the capacity to distinguish fine detail in an image.

• magnification
• resolution
• microscopy
• cell fractionation

Lysosomes are small sacs containing (a)   enzymes that can break down (lyse) complex molecules. foreign substances, and "dead" organelles.

A nanometer is

• one millionth of a centimeter

• one millionth of a millimeter

• one millionth of a micrometer

Cell membrane functions include

• isolation of chemical reactions

• selective permeability

• moderating between a cell's internal environment and external environment

• maintaining cell shape

• concentration of reactants

The high resolution attained by the electron microscope is attributed to its use of

• fixed specimens

• electromagnetic lenses

• short wavelengths

• grid patterns

• electrons instead of light

Cells are small at least in part because as size increases the surface-to-volume ratio

• doubles

• decreases to half

• increases

• decreases

• reduces efficiency of cell activities

The Golgi complex functions to

• modify proteins

• process proteins

• package glycoproteins

• sort molecules

• break down large carbohydrates

Which of the following cells contain plastids?

• animal

• plant

• some eukaryotic

• some prokaryotic

• algae

The cell theory states that

• new cells come from preexisting cells

• all cells are descended from ancient cells

• cells divide

• living things are composed of cells

• cells contain genetic material

Ribosomal RNA is synthesized in the

• cytoplasm

• nuclear matrix

• cristae

• mitochondria

• nucleolus