BIO 100 - EXAM 1 (Exam, Review & Quizzes)

How does the diameter of a prokaryotic cell compare with the diameter of a eukaryotic cell?

A prokaryote has one-tenth the diameter of a eukaryote.

Which vitamin is water soluble and cannot be synthesized by the body?

B and C

Which feature is found in both prokaryotic and eukaryotic cells?

DNA

Why is fiber important for a healthy diet?

Fiber helps maintain healthy cholesterol levels.

Why is carbon often involved in chemical bonding?

It can form bonds with four other elements.

Why is the cohesion of water important for biological systems?

It helps transport water from the roots to the leaves of the plants.

Why is oxygen considered highly electronegative?

It pulls electrons toward itself.

Why are minerals necessary micronutrients?

Minerals cannot be made by the body.

How do prokaryotic cells differ from eukaryotic cells?

Prokaryotic cells do not have a nucleus.

Imagine a balloon is made from a membrane that's permeable to water but not sugar molecules. How would the balloon be affected if it is filled with a 50% sugar solution and then placed in a beaker of water?

The balloon would get larger as it gains water.

How would the permeability of the phospholipid bilayer of plasma membranes be described?

The bilayer is differentially permeable.

Imagine a balloon is made from a membrane that's permeable to water but not sugar molecules. How would the concentration of sugar inside the balloon be affected if the balloon is filled with a 50% sugar solution and then placed in a beaker of water?

The concentration will decrease.

What happens when the concentration of a solute is equal on both sides of a plasma membrane?

The net movement of particles through the plasma membrane will stop.

Which components form the structure of the plasma membrane?

a double layer of phospholipids with embedded proteins

What is the basic structure of most lipids?

a glycerol head and up to three fatty acid tails

Which monomer units combine to form proteins?

amino acids

Which molecule requires the most ATP to be used for moving across a plasma membrane?

an ion moving against a concentration gradient

Which example is an element?

calcium

Which substance uses a transport protein to pass through a plasma membrane?

calcium ions

What molecule is composed of one or more sugars?

carbohydrate

Which group of nutrients includes milk sugar (lactose)?

carbohydrates

Which macronutrient is the major source of energy for cells?

carbohydrates

Which element is the basis for the macromolecules found in living things?

carbon

Which feature is found in prokaryotic cells?

cell wall

Which cell component has barrel-shaped rings of microtubules to anchor structures and move chromosomes during animal cell division?

centriole

Which organelle is found in animal cells but not in plant cells?

centriole

Which organelle performs photosynthesis?

chloroplast

Which organelle is found in plant cells but not in animal cells?

chloroplast, central vacuole, cell wall

What type of chemical bond joins adjacent nucleotides along the length of a strand of DNA?

covalent bonds

What kind of bond is found between the individual atoms of a single water molecule?

covalent bonds that are polar

What protein fibers help form the framework of structural support for cells?

cytoskeletal elements

During diffusion, how do the solute molecules move?

down a concentration gradient of solute molecules

Although viruses are extremely small, they are too large to enter a cell by passive transport. Which process brings viruses into a host cell?

endocytosis

Which of the following is not located in the nucleus?

endoplasmic reticulum

How would amino acids and calcium ions from the bloodstream move across a plasma membrane?

facilitated diffusion

Which food would contain all essential amino acids?

fish

What is the ability of living things to maintain a relatively constant internal environment?

homeostasis

What kind of bond holds two water molecules to each other?

hydrogen bonds

What type of chemical bond connects the complementary strands of a DNA molecule to each other?

hydrogen bonds

Which process does not involve molecules moving across cell membranes?

hydrogenation

What characteristic applies to the interior of a phospholipid bilayer?

hydrophobic

Sodium chloride is composed of molecules that are stable when dry. In water, the atoms of the molecules separate from each other. What type of chemical bond holds the dry substance together?

ionic bonds

Imagine a newly discovered biological molecule that is mostly hydrophobic in its structure. How would this new molecule be classified?

lipid

Which organelle contains digestive enzymes that degrade macromolecules?

lysosome

What are nutrients that the human body requires in large quantities?

macronutrients

Which feature is present in all known living things?

metabolic reactions

Which organelle performs cellular respiration?

mitochondrion

What is diffusion?

molecules moving from high concentrations to low concentrations

Which problem might result from decreases in a body's normal water level?

muscle cramps

Which particles are found in the nucleus of an atom?

neutrons and protons

Which macromolecule has a sugar-phosphate backbone?

nucleic acid

In which eukaryotic cell structure are ribosomes made?

nucleolus

Which monomer units combine to form nucleic acids?

nucleotides

What atoms may form a hydrogen bond?

one hydrogen atom and one partially negative atom

How are large substances moved during exocytosis?

out of the cell

Which process involves the movement of molecules or atoms down a concentration gradient across plasma membranes?

passive transport

What kind of molecule forms the bilayer found in cellular membranes?

phospholipid

Some antibiotics disrupt bacterial phospholipids. Which cell component would be affected by such antibiotics?

plasma membrane

Which chemical condition describes the electrons in a water molecule being shared unequally between the hydrogen and oxygen atoms?

polar

Which substance is a micronutrient?

potassium

What type of molecules, embedded in phospholipid bilayers, transport hydrophilic molecules into or out of the cell?

proteins

What does "hydrophobic" mean?

repelled by water

Which organelle is a network of membranes involved in the production of proteins?

rough endoplasmic reticulum

Which type of lipid includes sex hormones such as testosterone and estrogen?

steroids

Which monomer units combine to form polysaccharides?

sugars

What is facilitated diffusion?

the movement of molecules across a membrane, assisted by proteins embedded in the membrane

What is osmosis?

the movement of water across a membrane

Which component of amino acids accounts for the differences in their properties?

the side group

What is a function of antioxidants?

to decrease damage done to cells by free radicals

Assume that a plant is suffering from drought and is beginning to wilt. Which cell component is most likely being affected, and what type of molecule is being lost from this structure?

vacuole; water