Biology

DNA and RNA differ in that

DNA is double-stranded and contains the sugar deoxyribose and the nitrogen-containing base thymine; RNA is single-stranded and contains sugar ribose and the nitrogen-containing base uracil.

Which of the following is not a property of water?

It is denser when frozen than when liquid.

Which statement regarding the scientific method is false?

Original hypotheses are formed after an experiment.

Which of the following statements is not true with respect to scientific theory?

Theories are possible explanations for natural events.

Living organisms do the following

They respond to the environment they grow and develop They use materials and energy

How are lipids different from other categories of biological molecules?

They will not combine with water.

ATP releases energy when

a phosphate is removed.

The part of the enzyme into which the substrate fits is called the

active site

Which of the following is not a function of the endomembrane system?

acts as the control center of the cell

Enzymes are named based on the substrate that they bind. This is possible because

an enzyme binds one specific substrate.

Mitochondria and chloroplasts are similar in that they both ________, but are different in that mitochondria, but not chloroplasts, ________.

are involved in energy conversions; are found in nearly all eukaryotic cells

Mitochondria are found in

both plant cells and animal cells.

A(n) ________ can be defined as a substance that prevents the pH of a solution from changing by either releasing or absorbing H + in a solution.

buffer

____________is the smallest unit of living organisms

cell

The pH scale is a mathematical indicator of the

concentration of H + present in a solution.

The principle role for sugars in living things is to

create cellular energy.

All cells have some characteristics in common; both prokaryotic and eukaryotic cells have

cytoplasm, a plasma membrane, and DNA.

A prokaryotic cell

does not have a membrane-bound nucleus.

A covalent bond occurs when

electrons are shared between two atoms to complete their octets.

Which one of the following is a function of proteins?

energy storage

Atherosclerosis is associated with

fats with no double bonds.

Which of the following is not one of the most common elements in living things?

iron

What is the function of a peptide bond?

joins an amino acid to an adjacent amino acid

Which of the following is a correct matching of an organelle and its function?

mitochondrion - cellular respiration

There is an antibiotic called streptomycin that doctors prescribe for infection. The antibiotic combines with the bacteria's ribosomes causing them to lose their function. Consequently, the cells die and the person gets better. In other words, the antibiotic destroys bacteria by

not allowing them to produce proteins.

Select the incorrect association.

proteins—have three forms: monosaccharides, disaccharides, and polysaccharides

Which of the following organelles is not surrounded by a membrane?

ribosomes

Which of the following is an incorrect match?

smooth endoplasmic reticulum - storage of water

Cell size is limited because ________ is critical to a cell's function.

surface-area-to-volume ratio

Which of the following is not a type of potential energy?

the energy of a ball rolling down a hill

Less energy is needed to bring about a reaction when an enzyme is present.

true

Proteins within the extracellular matrix play a role in communicating between the matrix and the cytoskeleton.

true

The hydrophilic parts of the plasma membrane face the outside of the cell and the cytoplasm.

true