Chapter 3 Cells

Which of the following solutions are isotonic for normal human red blood cells?

0.9% NaCl solution

The body of an average sized adult human contains approximately

100 trillion cells

The human somatic cells contain ___ chromosomes.

46

Unlike active processes, passive processes do not require

ATP

Which is true of transcription?

DNA is used to make mRNA during transcription.

During which phase of cell division labeled in the diagram is cytokinesis completed?

E

All cells in the human body contain a single centrally located nucleus.

False

Endocytosis results in the secretion of contents outside of a cell.

False

Facilitated diffusion requires a membrane carrier protein and cellular energy.

False

In passive transport, the net result is that solutes move from an area of low solute concentration to an area of higher solute concentration.

False

Most proteins can easily move across the lipid bilayer of the plasma membrane.

False

Passive transport requires the use of cellular energy (e.g. ATP) but active transport does not.

False

Peripheral proteins penetrate all the way through the phospholipid bilayer of the plasma membrane.

False

Reproductive cell division allows new cells to replace injured or dead body cells.

False

Ribosomes consist of three subunits of equal size.

False

The cytosol includes the organelles.

False

The main functions of rRNA occur in the nucleus.

False

The nucleus acts as barrier between a cell's internal and external environment.

False

Usually only one mutation is needed to convert a non-cancerous adenoma into a cancerous carcinoma.

False

A CGT base triplet within a gene on DNA is transcribed into mRNA as

GCA

The _____ is an organelle consisting of flattened sacs where proteins are modified and packaged into vesicles.

Golgi complex

Which of following organelles is primarily involved in the modification (e.g. glycosylation), sorting, and packaging of proteins?

Golgi complex

Which of the following statements are TRUE for the plasma membrane?

It is selectively permeable and contains glycoproteins and cholesterol.

A base triplet of AUG on mRNA would match the anticodon_____ on tRNA

TAC

Why is the nucleus so important in the life of a cell?

The nucleus contains genes which determine all cellular activities.

Which statement about cells is TRUE?

The shape of a cell is related to its function.

Cytosine is found in both DNA and RNA and it only hydrogen bonds with a complementary nitrogenous base called guanine.

True

During interphase, a cell replicates its DNA and does most of its growing.

True

Each organelle has its own unique set of enzymes.

True

Normal cells grown outside the body divide a certain number of times and then stop dividing, suggesting this is a normal, programmed event.

True

Osmotic pressure is the pressure that builds up inside a cell and resists net water movement across its membrane.

True

Protective ends of chromosomes called telomeres shorten with each cycle of cell division.

True

Protein synthesis begins with a DNA code in the nucleus. DNA is copied as an mRNA strand. The mRNA goes to the ribosome where tRNA brings in the appropriate amino acids. These amino acids bond to form a protein. The process continues until the stop codon is read.

True

Protein synthesis is the assembling of individual amino acids into long, complex molecules according to nucleotide sequences on mRNA.

True

The Golgi complex produces some of the components of lysosomes.

True

The first stage of mitosis is called prophase.

True

The nucleus can communicate with the cytosol via nuclear pores in the nuclear envelope.

True

The only type of cell in the human body that contains a flagellum is a sperm cell.

True

The plasma membrane is selectively permeable because it allows fat soluble substances to pass through without assistance but requires channels and carrier proteins to move charged particles from one side to the other.

True

The term cytoplasm refers to all cellular contents between the plasma membrane and the nucleus.

True

Virtually all cervical cancers in women are caused by an oncogenic virus called human papillomavirus (HPV).

True

Which of the following is necessary for simple diffusion to take place?

a concentration gradient

Solute molecules can be transported from an area of low solute concentration to an area of higher solute concentration by_______-transport

active

Endocytosis is an example of

active transport

The characteristics of each individual protein are based on their sequence of

amino acids

The lipid bilayer of the plasma membrane is permeable to all of the following substances EXCEPT

amino acids

Which phase of somatic cell division involves the splitting of centromeres followed by separating the two resultant members of each chromatid pair?

anaphase

An orderly, genetically programmed cell "death" involving activation of "cell-suicide" genes is called

apoptosis

The process by which worn-out cellular organelles are digested is called

autophagy

The basic chemical framework of the plasma membrane is the lipid

bilayer

The primary role that integral membrane proteins play in active transport is to

bind and transport solute molecules against the concentration gradient.

A disease characterized by uncontrolled or abnormal cell proliferation is called

cancer

A chemical agent or radiation that causes cancer is referred to as a(n)

carcinogen

The multistep process by which cancer develops is referred to as

carcinogenesis

Glycoproteins and glycolipids in the plasma membrane serve as

cell identity markers

The movement of solute molecules across a plasma membrane from an area of low solute concentration to an area of high solute concentration requires

cellular energy and integral proteins

An organelle located near the nucleus that consists of two cylindrical structures composed of clusters of microtubules is called the

centrosome

Which of the following does NOT describe the cytoplasm?

controls most cellular activities

The shrinkage that occurs when cells are placed into a hypertonic solution is called

crenation

During somatic cell division, the process in which the cytoplasm and its organelles are divided is referred to as

cytokinesis

Microfilaments, microtubules, and intermediate filaments are all part of an intracellular network called the

cytoskeleton

The liquid portion of the cytoplasm is called the

cytosol

Jennifer loves perfume. She visits her local discount store regularly. Today she came to class wearing her latest purchase and soon everyone in the entire classroom was familiar with the scent. What concept important to transport processes is being demonstrated here?

diffusion

The nucleus is enclosed by the nuclear

envelope

Which of the following types of cells contain microvilli to increase the surface area of their plasma membrane for absorption?

epithelial cell of the small intestine

A normal red blood cell that is placed into a hypotonic solution will

gain water

The branch of medicine dealing with medical issues of aging is called

geriatrics

The study of the processes and problems associated with aging is called

gerontology

When solutes move from an area of high concentration to an area of low concentration, they are moving down their concentration

gradient

In somatic cell division, the phase in which the DNA is replicated is called

interphase

The type of body fluid found in the microscopic spaces between cells of tissues is called

interstitial fluid

A solution containing the same concentration of water molecules and solutes as a red blood cell is considered to be a(n)_____solution

isotonic

The organelle that contains as many as 60 different digestive enzymes is called the

lysosome

Chromatid pairs line up in the center of a cell during the stage of mitosis called

metaphase

The spread of cancerous cells to other parts of the body is referred to as

metastasis

Which of the following intracellular structures is considered to be part of the cytoskeleton?

microtubules

Cristae are a series of folds in the inner membrane of

mitochondria

The cellular organelle primarily responsible for transforming the chemical energy found in nutrients into ATP is the

mitochondria

Which of the following organelles are commonly referred to as the "powerhouses" of a cell?

mitochondria

The football-shaped assembly of microtubules that is used to move chromosomes to opposite poles of a dividing cell is called the

mitotic spindle

In a mature human body, which of the following types of cells do not divide?

nerve cells

Which of the following statements correctly describes the events that occur when a normal red blood cell is placed in a hypotonic solution?

net movement of water molecules into a cell

Chromatin is found in the

nucleus

The study of tumors is called

oncology

Water moves through a selectively permeable membrane using the process of

osmosis

Proteins loosely attached to the interior or exterior surface of the cell membrane are called ________________proteins.

peripheral

Certain white blood cells can destroy bacteria using the process of

phagocytosis

The plasma membrane consists of

phospholipids, proteins, and carbohydrates

Pinocytosis and phagocytosis involve structural changes in the

plasma membrane

To initiate the transcription of a gene, RNA polymerase binds to a _____, which is usually found near the beginning of the gene.

promoter

All of the following are associated with mitochondria EXCEPT

proteasomes

Meiosis is also called_____________cell division

reproductive

Which of the following statements BEST describes essential characteristic(s) of active transport?

requires both a pump and cellular energy

Which of the following statements is always true for active transport processes and never true for passive transport processes?

requires energy in the form of ATP

Which of the following statements is NOT TRUE with regard to the cytoplasm?

responsible for nuclear division during mitosis

The protein synthesis process called translation requires

ribosomes

The synthesis of plasma membrane proteins occurs in ribosomes attached to the outer surface of the

rough endoplasmic reticulum

Which of the following organelles in liver cells contains enzymes that help to detoxify drugs and potentially harmful substances in the blood?

smooth ER

Which of the following organelles is the site of synthesis of steroid hormones like estrogens and testosterone?

smooth endoplasmic reticulum

The type of cell division that produces two identical cells is called

somatic cell division

Meiosis is the type of cell division used during the formation of

sperm cells

When translation of a particular protein is complete, termination of protein synthesis is indicated by the presence of a(n)

stop codon

Which of the following statements are true of BOTH simple diffusion and facilitated diffusion?

substances move down their concentration gradient and no ATP is required

The major function of the ribosomes is to

synthesize proteins

Amino acids that participate in protein synthesis are picked up in the cytosol by

tRNA

The anticodon is located on the

tRNA

Specific DNA sequences at the tips of chromosomes that protect the chromosomes from erosion and sticking together are called

telomeres

The final stage of mitosis in which a nuclear envelope forms around the two new chromatin masses is called

telophase

The cytoplasm is a term that refers to

the cytosol plus cell organelles

Which of the following does NOT occur as a result of cellular aging?

the length and number of telomeres on the ends of DNA increases

The two major steps in synthesis of a protein based on the sequence of nucleotides in a gene are

transcription, translation

Which of the following is a protein that promotes the growth of new networks of blood vessels that support tumor growth?

tumor angiogenesis factor

All of the following are nucleotide bases commonly found in DNA molecules EXCEPT

uracil

Which of the following is a component of RNA only?

uracil

A semipermeable membrane, which permits water movement but not ion movement, separates two solutions. Solution A contains 0.9% NaCl and solution B contains 9.0 % NaCl. With respect to this system, which of the following statements would be true?

water would move from solution A to solution B