The Cell Review

Which of the following types of cell transport requires energy?

The transport of a particle across a selectively permeable membrane against its concentration gradient.

When a substance is transported across the cell membrane across the concentrations gradient (from an area of low concentration to an area of high concentration), this is referred to as __________.

active transport

Passive transport that relies on transport proteins to allow molecules to pass through the cell membrane is called __________.

Facilitated diffusion is the type of passive transport that relies on transport proteins embedded in the cell membrane. No energy is used in this transport since the molecules follow their concentration gradients so it is not active transport. Osmosis refers to passive movement of water only.

Which of the following is the term used for the model that describes the cell membrane as a mix of proteins bobbing about in a fluid bilayer of phospholipids?

Fluid Mosaic Model

Which of the following organelles is known as the transport and processing center?

Golgi apparatus

What term describes the tendency of an organism to maintain a relatively stable equilibrium between interdependent elements in its internal environment?

Homeostasis

When comparing two solutions with different solute concentrations, which of the following best defines the solution with the higher concentration of solute?

Hypertonic

When comparing two solutions with different solute concentrations, which of the following best defines the solution with the lower concentration of solute?

Hypotonic

What occurs during endocytosis?

The cell takes in material from outside the cell by enveloping the material and ingesting it.

What is the term that describes when a cell expends energy to pump molecules across its membrane against their concentration gradients?

Active transport occurs when the cell uses energy to pump molecules into and out of the cell against their concentration gradients.

Which of the following terms best describes a phospholipid that has both a hydrophilic region and a hydrophobic region?

Amphipathic Molecule

Eukaryotic cells have this structure that is a network of protein filaments that helps the cell to maintain its shape.

Cytoskeleton

Which of the following terms is best defined as the tendency of molecules to spread out into available space?

Diffusion

Which of the following are types of endocytosis?

Endocytosis is the process by which the cell takes in macromolecules by creating new vesicles from the cell's plasma membrane. Phagocytosis, pinocytosis, and receptor-mediated endocytosis are all different types of endocytosis.

Which of the following proteins act as a carrier for transporting substances across the cell membrane?

Integral protein

Which of the following terms is used to describe the transmembrane proteins that span the hydrophobic interior of the cellular membrane?

Integral proteins

A scientist is given two solutions, solution A and solution B. Solution A has the same number of total solutes, but solution B has a greater variety solutes. In comparison to solution A, solution B is __________.

Isotonic

Which of the following best describes solutions of equal solute concentrations?

Isotonic

Of the following organelles, which contains hydrolytic enzymes that can break down cellular debris?

Lysosome

Which of the following organelles is present only in animal cells?

Lysosomes

Which of the following organelles generates, stores, and releases energy for cell activities?

Mitochondria

In eukaryotes the organelles that convert energy to forms the cells can use for work are __________.

Mitochondria and Chloroplast

regard to cellular membranes, what does it mean to be selectively permeable?

Molecules and ions outside the cell are selected to enter the cell via active or passive transport through the phospholipid bilayer

In facilitated diffusion, what occurs in the cell?

Molecules, such as glucose, move through protein channels from an area of higher concentration to lower concentration

Ribosomes are macromolecular structures composed of both proteins and RNAs. Where are the ribosomal RNAs synthesized in eukaryotic cells?

Nucleolus

In order for a solute to pass through a cell membrane via diffusion, it must be all of the following except __________.

Only small, uncharged molecules that are nonpolar can cross the cell membrane via diffusion. For example, oxygen molecules can easily diffuse across the cell membrane.

Which of the following is an example of passive transport?

Osmosis

Which of the following terms is best defined as diffusion of water across a selectively permeable membrane?

Osmosis

Which of the following best characterizes the process of osmosis?

Passive Transport

Nonpolar molecules will typically pass though the plasma membrane via which mechanism?

Passive diffusion

A small molecule passes through the phospholipid bilayer without consuming ATP in the process. This is an example of which of the following?

Passive transport; no energy is required when a molecule moves down its concentration gradient.

Which of the following is best described as an example of a selective barrier in a cell?

Plasma Membrane

Which part of the cell separates the internal parts of the cell from the external environment?

Plasma Membrane

Which of the following molecules cannot pass through the membrane spontaneously?

Plasma membranes are selectively permeable. Small non polar molecules like molecular oxygen and hydrocarbons can pass through the membrane while larger charged molecules like glucose cannot, unless their transport is facilitated by a membrane protein.

The Golgi apparatus is responsible for which function of the cell?

Protein packaging

What is the cellular compartment responsible for the assembly of proteins?

Ribosomes

Ribosomes are the site of protein synthesis in both eukaryotes and prokaryotes. In eukaryotes, ribosomes can either be "free" or "bound." To which larger organelle are bound ribosomes attached?

Rough endoplasmic reticulum

The function of the sodium-potassium pump is an example of __________.

Sodium-potassium pumps are an example of membrane proteins that undergo active transport. They function by using ATP for energy to pump potassium and sodium against their respective concentration gradients.

A scientist is given two solutions, solution A and solution B. Solution A has a higher number of total solutes, but solution B has a greater variety of solutes. In comparison to solution B , solution A is __________.

Solution A is hypertonic to solution B. Solution A is hypertonic because it has an overall higher number of solutes in it even though B has more types of solutes in it. Diversity of the solutes does not matter when comparing concentrations of solutions, only the overall number of solutes matters. Tonicity can be thought of as relative concentration. Remember that a solution cannot simply be hypertonic or hypotonic; its concentration must be compared to that of another solution.

If an animal cell is placed in a solution that is hypertonic to the cell, the cell will __________.

The cell will lose water, shrink, and most likely die. When a cell is placed in a solution that is hypertonic to it, water will flow from the hypotonic inside of the cell to the hypertonic environment outside the cell. This causes the cell to shrink from water lost and die. Remember that water follows solutes.

If an animal cell is placed in a solution that is hypotonic to the cell, the cell will __________.

The cell will take in water and most likely burst, killing the cell. When a cell is placed in a solution hypotonic to it, water will flow from the hypotonic surroundings into the hypertonic cell. This causes the cell to grow with water intake until it bursts like a water balloon.

A microscopic view of a cell shows a dense, rigid exterior. Which of the following types of cells is least likely being observed?

The dense, rigid exterior is most likely describing a cell wall. Cell walls are used to protect cells and help them maintain their shape. Plant cells, fungal cells, and most prokaryotic cells have a cell wall structure, though the composition of the cell walls varies between cell types

The endomembrane system, which is responsible for regulation of protein traffic and performs metabolic functions, consists of what combinations of organelles?

The endomembrane system consists of the nuclear envelope, endoplasmic reticulum, Golgi apparatus, lysosomes, vacuoles, and plasma membrane.

Which of the following organelles manufactures lipids and proteins?

The endoplasmic reticulum is an organelle that manufactures proteins, steroid molecules, cholesterol, and other lipid

What occurs during exocytosis?

The membrane of the vacuole fuses with the cell membrane, forcing the contents out of the cell.

Which of the following is the function of the nucleolus?

The nucleolus is a specialized structure within the nucleus that is the site of ribosome synthesis and assembly. The nucleolus is not directly involved in DNA replication, translation, or ATP synthesis. While the DNA of eukaryotic cells is stored in the nucleus, it is not stored in the nucleolus since this part of the nucleus is specialized for ribosome assembly.

Which of the following organelles plays a key role in protein translation?

The rough endoplasmic reticulum is given its name due to the ribosomes present within its membrane

Which of the following are true regarding animal cells?

They have many small vacuoles

A scientist is given two solutions, separated by a semi-permeable membrane that allows for the passage of water but not solutes. Solution A only has one type of solute and has a higher overall concentration than solution B. Solution B has three different types of solutes in it. The net movement of water is towards __________.

Water will move towards the side the containing solution A. Solution A has a higher concentration of solutes so it is hypertonic to solution B and water will always move from a hypotonic solution towards a hypertonic solution even if the hypotonic solution has more types of solutes in it. The types of solutes is irrelevant for this case, only concentration of solutes matters. Remember: water follows solutes.

Mitochondria and chloroplasts have their own DNA, which is similar to the DNA of

bacteria

How does exocytosis work?

cells use vesicles to secrete substances from the cell

The process by which the cell secretes large macromolecules by the fusion of vesicles containing the macromolecules to the plasma membrane is called __________.

exocytosis

How does endocytosis work?

the cell takes in macromolecules by forming vesicles from the plasma membrane to carry the molecules into the cell.