Biology Chapter 3, Cells

How many layers of phospholipids make up the plasma membrane of a cell?

2

The energy for active transport usually comes from the breakdown of

ATP

Select all of the structures that you would expect to find in a prokaryotic cell.

DNA plasma membrane cytoplasm

True or false: A typical compound light microscope can be used to visualize the elements of the cell's cytoskeleton.

False

True or false: Although diffusion is a random movement of molecules, it sometimes requires energy.

False

True or false: Once the diffusion of molecules across a plasma membrane has resulted in equal concentrations (equilibrium) on either side of the membrane, the movement of molecules across the membrane ceases.

False

True or false: Sodium-potassium pumps function in bulk transport into and out of a cell.

False

Why does active transport require energy?

Molecules are being moved against the concentration gradient

Ribosomal RNA (rRNA) and ribosome subunits are produced in what dark region(s) of the nucleus?

Nucleoli

Which statement best describes the net movement of oxygen across the plasma membrane of a metabolically active animal cell?

Oxygen molecules are being consumed inside the cell, so there is a net movement of oxygen into the cell.

Which of the following is an example of active transport?

Sodium transport across a membrane

Which of the following best explains why placing cells into a hypertonic solution causes them to shrink?

Water rushes out of the cell

A hypertonic solution has ______ solute concentration than that of a cell.

a higher

An enzyme contains a specific region called the ______ where a substance called the ______ will bind.

active site substrate

ATP provides the energy required to fuel which of the following processes?

active transport

Molecules move from lower concentrations to areas of higher concentration during which of the following?

active transport

Which one of the following requires oxygen?

aerobic respiration

The best general definition of endocytosis is

an inward pinching of the plasma membrane to form a vesicle.

In 1898, Italian scientist Camillo Golgi discovered a cellular organelle that is named the Golgi

apparatus

Protein channels that allow water molecules to freely cross a membrane are called

aquaporins

Select all correct statements regarding facilitated transport.

carrier proteins are specific to a single type of molecule

Select all correct statements regarding facilitated transport. Multiple choice question.

carrier proteins are specific to a single type of molecule

The basic unit of life is the

cell

The smallest, most basic unit of life (the smallest thing that is considered to be alive) is a(n)

cell

Mitochondria are often referred to as the powerhouses of the cell because the major metabolic process that takes place there is

cellular respiration

The combination of DNA and proteins that forms visible chromosomes during cell division is called

chromatin

nucleus

contains chromatin with DNA

The cytoplasm of a eukaryotic cell is crisscrossed by several types of supportive protein fibers, which are collectively called the

cytoskeleton

Which of the following is responsible for maintaining the shape of the cell and for anchorage and movement of organelles?

cytoskeleton

The random movement of molecules from an area of higher concentration to an area of lower concentration is called

diffusion

lysosome

digests macromolecules and cell parts

Inside a cell, the organelles of the _______ system work together to transport molecules from one part of the cell to another.

endomembrane

The nuclear envelope, endoplasmic reticulum, Golgi apparatus, lysosomes, and vesicles make up the _______ system of a cell

endomembrane

The nuclear envelope of a cell connects most directly to which organelle?

endoplasmic reticulum

A vesicle fuses with the plasma membrane and secrete its contents into the extracellular space during the process of

exocytosis

When molecules move across the plasma membrane from areas of higher to lower concentration using a carrier protein, this is called

facilitated transport

True or false: Lysosomes are found only in white blood cells.

false

True or false: The first cells to evolve on earth were eukaryotic cells.

false

Which metabolic process can be used by cells to break down glucose when no oxygen is available, forming lactate plus 2 ATP?

fermentation

Which one of these is contained inside the nucleus of a eukaryotic cell?

genetic information

Select the biochemical pathways that are involved in the breakdown of glucose.

glycolysis citric acid cycle electron transport chain

polar heads

hydrophilic

non polar heads

hydrophobic

A solution that has a lower concentration of solutes and a higher concentration of water compared to a cell is said to be ____ to the cell

hypotonic

With regard to tonicity, two solutions that have the same concentrations of nondiffusible solutes and water are said to be

isotonic

A cell containing a certain concentration of salt is placed in a solution. The cell neither shrinks nor swells. Therefore, the solution is said to be

isotonic to the cell

Select all correct statements regarding the plasma membrane of a cell.

it allows only certain molecules and ions to enter and exit the cytoplasm freely it has a "sandwich" structure, with two phospholipid layers

Which of the following pass freely and easily through the plasma membrane? Select all that apply.

lipid-soluble molecules water (through aquaporins) small molecules

A hypotonic solution has ______ concentration of solute than a cell.

lower

Membranous sac-like cellular organelles that contain hydrolytic enzymes are called

lysomes

Select the five cellular organelles that are part of the endomembrane system.

lysosomes nuclear envelope vesicles endoplasmic reticulum Golgi apparatus

Select all functions of the cytoskeleton.

maintains cell shape assists in organelle movement anchors organelles

cytoskeleton

maintains cell shape, assists movement of cell parts

Collagen, elastin, and fibronectin are all components of the ECM or extracellular

matrix

vesicle

membrane-bounded sac; storage and transport

The overall term for all the chemical reactions that occur in a cell is

metabolism

In the metric system, 1/1,000 of a millimeter is equal to one

micrometer

centrosome

microtubule organizing center

Using units of the metric system, there are 1000 micrometers in one

millimeter

Which organelle is the main site of ATP synthesis?

mitochondrion

The structure that connects the nucleus to the endoplasmic reticulum is the

nuclear envelope.

The ribosomal RNA for ribosomes is produced by a dark region within the nucleus called the

nucleolus

The prominent structure in eukaryotic cells that stores the genetic information (chromosomes) is the

nucleus

The plasma membrane is selectively permeable, meaning that Multiple choice question.

only some substances can cross the membrane.

The net movement of water across a semipermeable membrane in response to differing solute concentrations on the two sides of that membrane is specifically called

osmosis

Cellular respiration, the biochemical process by which mitochondria convert the chemical energy of glucose (or other nutrients) into ATP, resembles the respiration carried out by human lungs in what two ways?

oxygen is taken up carbon dioxide is released

A series of enzymatic reactions that result in either the synthesis of a required product, or breakdown of a chemical substrate, is referred to as a metabolic

pathway

Because the plasma membrane of a cell allows only certain molecules and ions to enter and exit the cytoplasm, it is said to be selectively

permeable

White blood cells engulf pathogens by a process known as

phagocytosis

The process of taking pathogens into a white blood cell by forming a pouch from the plasma membrane is called

phagocytosis.

plasma membrane

phospholipid layer that regulates entry and exit of molecules

The type of endocytosis that brings relatively small molecules and liquids into the cell is

pinocytosis

Which of the following processes involve invagination of the plasma membrane in order to bring molecules into a cell? Select all that apply.

pinocytosis phagocytosis endocytosis

Which of the following applies to the formation of the phospholipid bilayer of the cell membrane? Select all that apply.

polar heads oriented to the outside and inside of the cell hydrophobic tails oriented inward toward each other heads face the watery sides of the membrane

The nuclear envelope has nuclear ______, of sufficient size to permit the passage of ribosomal subunits out of the nucleus and proteins into the nucleus.

pores

Golgi

processes and modifies cell products

rough ER

processes proteins

mitochondrion

produces ATP

Cells that lack a membrane-bound nucleus are called _______ cells. Multiple choice question.

prokaryotic

The first cells to evolve on Earth were what type?

prokaryotic

The fibers that make up the cytoskeleton of a cell are all made of

protein

ribosomes

protein synthesis

Chromatin, which coils tightly during cell division to form chromosomes, is made of which types of molecules?

proteins nucleic acids

Ribosomes are made of which two components?

rRNA proteins

Which of the following are locations where cilia can be found in the human body?

respiratory tract uterine tubes

The cellular organelles responsible for protein synthesis are the

ribosome

Endoplasmic reticulum (ER) that is studded with ribosomes is called ______ ER; that which lacks ribosomes is called _____ ER.

rough smooth

Which of the following are portions of the endoplasmic reticulum?

rough ER smooth ER

Which of the following are functions of the plasma membrane?

selectively regulate passage of materials keep the cell intact

centrioles

short cylinders made of microtubules

The general function of all enzymes is to

speed up chemical reactions

In the human body, flagella are found in which location?

sperm cells

smooth ER

synthesizes lipids

In exocytosis, a vesicle containing macromolecules fuses with

the plasma membrane

In multicellular organisms, cells are usually organized into _______, such as nervous and connective.

tissues

When water moves via osmosis across a selectively permeable membrane, the direction in which it will move is determined by the ______ of the solutions inside and outside of the cell, which is based on solute concentration of a solution.

tonicity.

Select the functions of the endomembrane system of cells.

transports molecules within cells compartmentalize chemical reactions

True or false: Viruses are not made of cells, therefore viruses are non-living.

true

Plasma membrane protein channels called aquaporins are specifically involved in the transport of

water