Week 2 - Cells

Question 1

What are the three main parts of a eukaryotic cell?

a) plasma membrane, organelles, cytoplasm
b) plasma membrane, organelles, nucleus
c) plasma membrane, cytoplasm, organelles
d) plasma membrane, cytoplasm, nucleus
e) plasma membrane, cytosol, organelles

Answer 1

d) plasma membrane, cytoplasm, nucleus

Question 2

The three main components of the lipid bilayer portion of a plasma membrane are

a) phospholipids, glycoproteins, and water.
b) proteins, cholesterol, and fatty acids.
c) cholesterol, triglycerides, and glycolipids.
d) phospholipids, cholesterol, and glycolipids.
e) phospholipids, cholesterol, and proteins.

Answer 2

d) phospholipids, cholesterol, and glycolipids.

Question 3

What are the nonpolar parts of phospholipids?

a) phosphate-containing head groups
b) fatty acid tail groups
c) Both the head and tail groups are nonpolar.
d) Neither the head nor tail groups are nonpolar.

Answer 3

b) fatty acid tail groups

Question 4

This type of membrane protein extends across the entire lipid bilayer of the plasma membrane touching both intracellular fluid and the extracellular fluid.

a) complement protein
b) transmembrane protein
c) peripheral protein
d) lipoprotein
e) All of these choices are correct.

Answer 4

b) transmembrane protein

Question 5

This type of membrane protein enables cells to catalyze specific chemical reactions at the inner or outer surface of their plasma membrane.

a) receptors
b) phospholipids
c) cholesterol
d) enzymes
e) ligands

Answer 5

d) enzymes

Question 6

This type of membrane protein anchors cells to neighboring cells and to protein filaments found outside or inside the cell.

a) transporters
b) receptors
c) ligands
d) ion channels
e) linkers

Answer 6

e) linkers

Question 7

Plasma membranes are ________, which means that some chemicals move easily through plasma membrane while other chemicals do not.

a) selectively permeable
b) concentration graded
c) electrically graded
d) selectively soluble
e) electrical insulators

Answer 7

a) selectively permeable

Question 8

Which of the following does NOT influence the rate of diffusion of a chemical across a plasma membrane?

a) concentration gradient of the chemical across the membrane
b) mass of the diffusing chemical
c) distance that the chemical has to diffuse
d) amount of ATP available
e) temperature

Answer 8

d) amount of ATP available

Question 9

This is a measure of a solution’s ability to change the volume of cells by altering their water content.

a) filtration
b) normality
c) tonicity
d) equivalency
e) facilitation

Answer 9

c) tonicity

Question 10

This is the transport process by which gases, like O2 and CO2, move through a membrane.

a) osmosis
b) active transport
c) secondary active transport
d) simple diffusion
e) endocytosis

Answer 10

d) simple diffusion

Question 11

In this type of transport process, a solute (e.g. glucose) binds to a specific carrier protein on one side of the membrane. This binding induces a conformational change in the carrier protein that results in the solute moving down its concentration gradient to the other side of the membrane.

a) osmosis
b) active transport
c) secondary active transport
d) facilitated diffusion
e) endocytosis

Answer 11

d) facilitated diffusion

Question 12

In this transport process, the energy from hydrolysis of ATP is used to drive substances across the membrane against their own concentration gradients.

a) primary active transport
b) secondary active transport
c) facilitated diffusion
d) passive diffusion
e) osmosis

Answer 12

a) primary active transport

Question 13

What transport process uses the energy stored in a Na+ or H+ concentration gradient to drive other substances across the membrane against their own concentration gradients?

a) primary active transport
b) secondary active transport
c) facilitated diffusion
d) passive diffusion
e) osmosis

Answer 13

b) secondary active transport

Question 14

During phagocytosis, binding of a particle to a plasma membrane receptor triggers formation of ________, which are extensions of the plasma membrane of the phagocyte that eventually surround the particle forming a phagosome.

a) podocytes
b) exterior vesicles
c) interior vesicles
d) pseudopods
e) lysosomes

Answer 14

d) pseudopods

Question 15

Which of the following is NOT a characteristic of the cytosol?

a) primarily consists of water
b) cation of electron transport chain carrier proteins
c) site of many important chemical reactions
d) often contains aggregates of triglycerides that form lipid droplets
e) contains the enzymes of glycolysis

Answer 15

b) cation of electron transport chain carrier proteins

Question 16

Spermatozoa is the only type of human cell that contains a ________, which is a whip-like structure that helps propel the sperm towards an oocyte.

a) cilium
b) flagellum
c) mitochondria
d) centrosome
e) microvillus

Answer 16

b) flagellum

Question 17

Which of the following membrane-enclosed organelles contains several oxidases that are involved in oxidation of fatty acids and amino acids during normal metabolism and in detoxification of chemicals like alcohol in the liver?

a) peroxisomes
b) mitochondria
c) proteasome
d) ribosomes
e) lysosomes

Answer 17

a) peroxisomes

Question 18

Which of the following membrane-enclosed organelles can engulf a worn-out organelle, digest its chemical components, and recycle those digested components?

a) peroxisomes
b) mitochondria
c) proteasome
d) ribosomes
e) lysosomes

Answer 18

e) lysosomes

Question 19

The major function of proteasomes is to

a) perform extracellular digestion of proteins.
b) perform autophagy.
c) digest dietary proteins for use by other organelles.
d) degrade unneeded, damaged or faulty cellular proteins.
e) degrade excess ATP.

Answer 19

e) degrade excess ATP.

Question 20

This process is division of the cytoplasm.

a) mitosis
b) meiosis
c) cytokinesis
d) cytosol
e) centrioles

Answer 20

c) cytokinesis

Question 21

During this phase of cell division, organelles duplicate and centrosome replication begins.

a) interphase
b) prophase
c) metaphase
d) anaphase
e) telophase

Answer 21

a) interphase

Question 22

How long does the G2 phase normally last?

a) 8 to 10 hours
b) 4 to 6 hours
c) 2 to 4 hours
d) 24 hours
e) 1 to 2 days

Answer 22

b) 4 to 6 hours

Question 23

During this phase of cell division, the chromatin fibers condense and shorten into chromosomes that are visible under the microscope.

a) interphase
b) prophase
c) metaphase
d) anaphase
e) telophase

Answer 23

b) prophase

Question 24

During this phase of cell division, the centromeres split leading to separation and subsequent migration of the two members of a chromatid pair to opposite poles of the cells. The cleavage furrow also begins to develop during this phase.

a) interphase
b) prophase
c) metaphase
d) anaphase
e) telophase

Answer 24

d) anaphase

Question 25

Most intravenous solutions are _________ with respect to blood cells?

a) tonicity
b) isotonic
c) hypertonic
d) osmotic
e) hypotonic

Answer 25

b) isotonic

Question 26

A patient would be infused with a _______ solution in order to ultimately relieve excess interstitial fluid in the brain.

a) tonicity
b) isotonic
c) hypertonic
d) hemolytic
e) hypotonic

Answer 26

c) hypertonic

Question 27

This is the site of synthesis of rRNA and assembly of rRNA and proteins into ribosomal subunits.

a) nucleus
b) nucleolus
c) smooth endoplasmic reticulum
d) rough endoplasmic reticulum
e) Golgi complex

Answer 27

b) nucleolus

Question 28

The difference in concentration of a specific chemical, like Na+, on the inside and outside of a plasma is referred as a(n)

a) electrochemical potential.
b) membrane potential.
c) electrical gradient.
d) concentration gradient.
e) biological capacitance.

Answer 28

d) concentration gradient.

Question 29

An orderly, genetically programmed cell death is referred to as ________, while disorganized pathological cell death is referred to as ________.

a) apoptosis; synapsis
b) apoptosis; necrosis
c) necrosis; apoptosis
d) synapsis; necrosis
e) necrosis; synapsis

Answer 29

b) apoptosis; necrosis

Question 30

The human body contains approximately __________ cells, which can be classified into about __________ different cell types.

a) 1 billion; 200
b) 1 trillion; 200
c) 100 trillion; 200
d) 1 trillion; 4
e) 100 trillion; 4

Answer 30

c) 100 trillion; 200