BIO 111 Test Final Dr. True Ball State

in comparison to eukaryotes, prokaryotes...

are smaller

which of the following types of cells utilize deoxyribonucleic acid (DNA) as the genetic material but do not have their DNA encased within a nuclear envelope

archean

in bacteria, DNA will be found in...

the nucleoid

which of the following are found in plant, animlal, and bacterial cells

ribosomes

which of the following order is correct in terms of the hierarchy of the organism

biosphere> ecosystem> community> population> organism

the phylogenetic tree...

includes every single life form on this earth

a friend of yours calls to say his car owuld not start this morning and ask for your help. You say that you think the battery is dead. If so, then jumping the car from a good battery will solve the problem. you are...

starting a hypothesis and using that hypothesis to make a testable prediction

in a controlled experiment the independent variable is the variable that is manipulated

true

bacteria, eukarya, protista are the three domains of life

false

the study of life is...

biology

a... is a testable explanation or observation

hypothesis

atoms have no electric charge because they have

an equal number of protons and electrons

molybdenum has an atomic number of 42. Several common isotopes include numbers from 92-100. Which of the following can be true?

Molybdenum atoms can have between 50 and 58 neutrons

what element does not prefer to react w other elements

helium

nitrogen (N) is more electronegative than hydrogen (H). Which of the following is the correct statement about the atoms in ammonia (NH3)

each hydrogen atom has a partial positive charge; the nitrogen atom has a partial negative charge.

How is a single covalent bond formed?

two atoms share two electrons

A compound is the smallest unit of matter.

False

The first orbital is the 1p orbital.

false

Table salt uses __________ bonds to bind the Na and Cl ions together.

ionic

Partial positive and partial negative charges are depicted using the Greek letter ________.

delta

The partial negative charge at one end of a water molecule is attracted to the partial positive charge of another water molecule. What is this attraction called?

a hydrogen bond

Sulfur is in the same column of the periodic table as oxygen, but has electronegativity similar to carbon. Compared to water molecules, molecules of H2S will ________.

not form hydrogen bonds with each other

Hydrophobic substances such as vegetable oil are ________.

nonpolar substances that repel water molecules

Based on your knowledge of the polarity of water molecules, the solute molecule depicted is most likely ________.

positively charged

As the [H3O+] of the solution decreases, the [OH-] ________.

increases and thus pH increases

In a water molecule, two hydrogen atoms are bonded to a single oxygen atom by hydrogen bonds.

False

A solution with a pH of 9.7 is basic.

True

A ____________ is a substance that minimizes pH changes.

buffer

A molecule that has affinity for water is known as _____________.

hydrophilic

Why is carbon so important in biology?

It can form a variety of carbon skeletons and host functional groups.

A carbon atom has 6 electrons however, its valency is 4. This is because the carbon atom ________.

has only 2 electrons in its first shell and 4 in the second shell

The two molecules shown in the figures are best described as ________.

structural isomers

Which molecule shown is a thiol?

B

Testosterone and estradiol are male and female sex hormones, respectively, in many vertebrates. In what way(s) do these molecules differ from each other? Testosterone and estradiol ________.

have different functional groups attached to the same carbon skeleton

Ketones and aldehydes are examples of chemicals with hydroxyls.

False

Carbon has 6 total electrons but only 4 valence electrons.

True

Isomers that are mirror images of each other are called ____________.

enantiomer

ATP stands for _________________.

adenosine triphosphate

Which of the following best summarizes the relationship between dehydration reactions and hydrolysis?

Dehydration reactions assemble polymers; hydrolysis reactions break polymers apart.

People who are lactose intolerant cannot extract energy from milk because

they are missing an enzyme

The molecule shown is ________.

a hexose

What makes lipids/fats hydrophobic

presence of relatively nonpolar C—H bonds

The molecule shown the figure is a ________.

steroid

Lysine is a hydrophobic amino acid.

False

Starch is a plant polysaccharide for storage, while glycogen is the animal equivalent.

True

Two glucose monomers joined together with a glycosidic bond form a __________ molecule.

maltose

The simplest amino acid is ____________ which only has a H as its side chain

glycine

Which of the following is a major difference between RNA and DNA?

type of sugar

Which of the following descriptions best fits the class of molecules known as nucleotides?

a nitrogenous base, a phosphate group, and a sugar

Which of the following molecules is a purine nitrogenous base?

13

The complex of DNA plus histone proteins together is known as ___________.

chromatin

A newspaper ad for a local toy store indicates that an inexpensive toy microscope available for a small child is able to magnify specimens nearly as much as the more costly microscope available in your college lab. What is the primary reason for the price difference?

The toy microscope magnifies a good deal, but has low resolution and therefore poor quality images.

Which of the following is a major difference between prokaryotic cells and eukaryotic cells?

Eukaryotic cells have membrane-bound organelles, while prokaryotic cells do not

Which domains of life are classified as prokaryotes?

Bacteria and Archaea

Which of the following macromolecules leave the nucleus of a eukaryotic cell through pores in the nuclear membrane?

mRNA

Examination of a cell by transmission electron microscopy reveals a high density of ribosomes in the cytoplasm. This observation suggests that this cell is actively producing large amounts of which of the following molecules?

proteins

The nuclear lamina is an array of intermediate filaments that line the inner side of the nuclear membrane. If a chemical treatment caused the lamina to disassemble, what would you expect to be the most likely immediate consequence?

a change in the shape of the nucleus

A cell with a predominance of rough endoplasmic reticulum is most likely ________.

producing large quantities of proteins for secretion

Which organelle often takes up much of the volume of a plant cell?

central vacuole

Which structure below is independent of the endomembrane system?

chloroplast

The liver is involved in detoxification of many poisons and drugs. Which of the following structures is primarily involved in this process and, therefore, abundant in liver cells?

smooth endoplasmic reticulum

Which of the following organelles produces and modifies polysaccharides that will be secreted?

Golgi apparatus

Asbestos is a material that was once used extensively in construction. One risk from working in a building that contains asbestos is the development of asbestosis caused by the inhalation of asbestos fibers. Cells will take up asbestos by phagocytosis, but are not able to degrade it. As a result, asbestos fibers accumulate in ________.

lysosomes

thylakoids, DNA, and ribosomes are all components found in ________.

chloroplasts

If plant cells are grown on media containing radioactively labeled thymine for one generation, radioactively labeled macromolecules will be detected in which of the following?

in the nucleus, mitochondria, and chloroplasts

Where are proteins produced other than on ribosomes free in the cytosol or ribosomes attached to the endoplasmic reticulum?

in mitochondria

Suppose a cell has the following molecules and structures: enzymes, DNA, ribosomes, plasma membrane, and mitochondria. It could be a cell from ________.

nearly any eukaryotic organism

Cyanide binds with at least one molecule involved in producing ATP. If a cell is exposed to cyanide, most of the bound cyanide is likely to be localized within the ________.

mitochondria

Suppose a young boy is always tired and fatigued, suffering from a metabolic disease. Which of the following organelles is most likely malfunctioning in this disease

mitochondria

Amoebae move by crawling over a surface (cell crawling), which involves ________.

growth of actin filaments to form bulges in the plasma membrane

Which of the following statements about the cytoskeleton is true?

Movement of cilia and flagella is the result of motor proteins causing microtubules to move relative to each other.

Which of the following structures form cytoplasmic channels that connect adjacent plant cells through the cell walls?

plasmodesmata

Ions can travel directly from the cytoplasm of one animal cell to the cytoplasm of an adjacent cell through ________.

gap junctions

H. V. Wilson worked with sponges to gain some insight into exactly what was responsible for holding adjacent cells together. He exposed two species of differently pigmented sponges to a chemical that disrupted intercellular junctions, and the cells of the sponges dissociated. Wilson then mixed the cells of the two species and removed the chemical that caused the cells to dissociate. Wilson found that the sponges reassembled into two separate species. The cells from one species did not interact or form associations with the cells of the other species.

How do you explain the results of Wilson's experiments?

The molecules responsible for cell-cell adhesion (cell junctions) differed between the two species of sponge.

The ___________ is a dense mass inside the nucleus where ribosomal RNA is synthesized.

nucleolous

The ______________ is the powerhouse of the cell.

mitochondria

The process known as __________ is where a cell recycles its own material from damaged organelles to use later.

autophagy

The _____________ theory explains how mitochondria and chloroplasts were engulfed and used by eukaryotes.

endosymbiont

___________ are cell junctions in plants that connect all cells and allow the cytosol to flow through.

Plasmodesmata

For a protein to be an integral membrane protein, it would have to be ________.

amphipathic, with at least one hydrophobic region

According to the fluid mosaic model, a membrane ________.

is composed of a fluid bilayer of phospholipids with embedded amphipathic proteins

An animal cell lacking carbohydrates on the external surface of its plasma membrane would likely be impaired in which function?

cell-cell recognition

Which of the following types of molecules are hydrophilic and therefore excluded from the hydrophobic portion of the phospholipid bilayer?

peripheral membrane proteins

Which of the following types of molecules lack hydrophilic domains?

cholesterol

Which of the following are least likely to diffuse through the phospholipid bilayer of a cell membrane?

small ions

Which of the following molecules dramatically increases the rate of diffusion of water across cell membranes?

aquaporins

Which of the following statements about diffusion is true?

It is a passive process in which molecules move from a region of higher concentration to a region of lower concentration.

When a cell is in equilibrium with its environment, which of the following processes occurs for substances that can diffuse through the plasma membrane?

There is random movement of substances into and out of the cell.

Which of the following statements correctly describes osmosis?

In osmosis, water moves across a membrane from areas of lower solute concentration to areas of higher solute concentration

The solutions in the arms of a U-tube are separated at the bottom of the tube by a selectively permeable membrane. The membrane is permeable to sodium chloride but not to glucose. Side A is filled with a solution of 0.4 M glucose and 0.5 M sodium chloride (NaCl), and side B is filled with a solution containing 0.8 M glucose and 0.4 M sodium chloride. Initially, the volume in both arms is the same.

In the U-tube experiment illustrated above, which of the following statements correctly describes side B at equilibrium?

The concentration of NaCl will increase, the concentration of glucose will decrease, and the water level will increase.

Celery stalks that are immersed in fresh water for several hours become stiff. Similar stalks left in a 0.15 M salt solution become limp. From this we can deduce that the fresh water ________.

is hypotonic and the salt solution is hypertonic to the cells of the celery stalks

Which of the following statements correctly describes the normal tonicity conditions for typical plant and animal cells? The animal cell is in ________.

an isotonic solution, and the plant cell is in a hypotonic solution

When a plant cell, such as one from a tulip leaf, is submerged in a hypertonic solution, what is likely to occur?

Plasmolysis will shrink the interior of the cell.

A sodium-potassium pump ________.

moves three sodium ions out of a cell and two potassium ions into a cell using energy from ATP hydrolysis

Which of the following membrane activities requires energy from ATP hydrolysis?

movement of Na+ ions from a lower concentration in a mammalian cell to a higher concentration in the extracellular fluid

Proton pumps are used in various ways by members of every domain of organisms: Bacteria, Archaea, and Eukarya. What does this fact most probably mean?

Proton gradients across a membrane were used by cells that were the common ancestor of all three domains of life.

Several epidemic microbial diseases of earlier centuries incurred high death rates because they resulted in severe dehydration due to vomiting and diarrhea. Today they are usually not fatal because we have developed which of the following types of treatments?

hydrating drinks with high concentrations of salt and glucose

The force driving simple diffusion is ________, while the energy source for active transport is ________.

a concentration gradient; ATP hydrolysis

White blood cells engulf bacteria using ________.

phagocytosis

Familial hypercholesterolemia is characterized by ________.

defective LDL receptors on the cell membranes