Biology 120 Exam 1 (Chapters 1-6) – Flashcards

Movement of materials among plant cells is made possible by

The membrane surrounding each organelle

If the inner membrane of a mitochondrion were not folded to create cristae,

Components of the cytoskeleton can be linked to all of the following functions of eukaryotic cells except

A specialized structure found in most, but not all, prokaryotes is the

All cellular membranes

The folds of the inner mitochondrial membrane

If you wanted to stain the ribosomes in a cell, you could use a dye that stains

If a cell is making a protein that is then going to be modified and packaged for export out of the cell, what is the order of structures it will most likely pass through?

A structure is considered extracellular if it

Lysosomes are important to eukaryotic cells because they contain

Mitochondria and chloroplasts differ in that

The function of the nuclear pores is to

Both tight junctions and desmosomes are abundant in epithelial tissues in animals, but their roles differ regarding

Steroids such as cholesterol are synthesized by

Ribosomes are made up of

Which best describes the chemical composition of a plant cell wall?

Which organelle is generated by the Golgi apparatus and contains digestive enzymes to hydrolyze macromolecules?

In mitochondria, the energy from "food" molecules (such as glucose) that is partially broken down in the cytosol is converted to

After a protein is made, what is one of the ways in which it can get to a specific location in a cell?

Which statement about the feedback inhibition of enzymes is false?

Which statement about the differences between DNA and RNA is false?

In an enzyme-catalyzed reaction,

A noncompetitive inhibitor may inhibit binding of a substrate to an enzyme by

The ability of an enzyme to change shape when it binds to its substrate is called

The statement "enzymes are highly specific" means that certain

Which solution is least likely to denature an enzyme?

An active site is

Almost all enzymes are

Which base is not found in DNA?

The process by which a final product acts as an inhibitor to the enzyme that catalyzes the commitment step in a metabolic pathway is called

A beta-pleated sheet organization in a polypeptide chain is an example of _______ structure.

The "skeleton" that makes up a nucleic acid molecule are made of

The shape of a folded protein is determined by

The four nitrogenous bases of RNA are abbreviated as

A protein can best be defined as a polymer

The molecules that are acted on by an enzyme are called

How do competitive and noncompetitive enzyme inhibitors differ?

Amino acids can be classified by the

When an egg is exposed to extreme heat it turns from a liquid substance into a solid substance. Even when the egg is allowed to cool, these changes are not reversible for a number of reasons. Which is not one of those reasons?

Sucrose, known as common table sugar, is a

Which list represents a correct ordering of the levels of complexity at which life is studied, from most simple to most complex?

Genes are

What can never be created or destroyed?

The general chemical formula for carbohydrates includes the atoms

The portion of a phospholipid that contains the phosphorous group has one or more electric charges, which make this region of the molecule

One reason we consider the dormant seed of a desert plant to be alive is that it

The monomers that make up polymeric carbohydrates like starch are called

Water held back by a dam represents what kind of energy?

The two atoms in a hydrogen molecule are held together by

The atomic number of an element is the same as the number of _______ in each atom.

Which component of an atom does not add significantly to its mass?

In a biological membrane, the phospholipids are arranged with the fatty acid chains facing the interior of the membrane. As a result, the interior of the membrane is

When exposed to extreme heat, the human body relies on _______ to absorb excess heat and maintain normal body temperature.

A single covalent chemical bond represents the sharing of how many electrons?

A type of molecule very often drawn with a single six-sided ring structure is

In condensation reactions, the atoms that make up a water molecule are derived from

Natural selection acts

The part of the atom that determines how the atom behaves chemically is the

Cholesterol is composed primarily of carbon and hydrogen atoms. Therefore, one would expect cholesterol to be

The hydrogen bond between two water molccules arises because water is

Plasma membranes are relatively impermeable to water-soluble molecules because

Osmosis

The difference between osmosis and diffusion is that

If a cell needs to acquire dissolved solutes continuously, which mechanism will most likely aid this process?

Plant cells transport sucrose across the vacuole membrane against its concentration gradient by a process known as

Many signal transduction pathways cause

Which of the following is not involved in secondary active transport?

Which of the following is not one of the functional roles of membrane proteins?

Active transport usually moves molecules

If a hospital patient is mistakenly given an IV of pure water instead of a saline solution that is isotonic to blood, the patient's red blood cells will

A protein that forms an ion channel through a membrane is most likely

The existence of a concentration gradient of glucose across a membrane means that

You are doing a summer internship in a cell biology lab. Your supervisor asks you to change the medium on some cells she is growing. You do so and then examine the cells under a microscope. To your dismay, you can't find any cells and see only what looks like cell debris. What most likely happened to your cells and why?

Which molecule acts as a second messenger in the cascade by which epinephrine stimulates the activation of the enzyme glycogen phosphorylase?

The rate at which a substance diffuses is not affected by the

The two sides of a membrane can be split apart from each other by an experimental technique known as freeze-fracturing. When one side of a freeze-fractured membrane is examined under the electron microscope, the exposed interior of the membrane bilayer appears to be covered with bumps. These bumps are most likely

Osmosis moves water from a region of _______ to a region of _______.

When placed in water, wilted plants lose their limpness because of

Osmosis is a specific form of

Which of the following is the driving force for simple diffusion?