Bio Exam 2

Photosynthesis is the process by which __________________ use the energy from sunlight to produce sugar.

chloroplasts

Chlorophyll b and the carotenoids are important as receptors of light energy because they:

respond to wavelengths different from the wavelengths that chlorophyll a responds to.

Cellular respiration is the process by which:

energy from the chemical bonds of food molecules is captured by an organism.

During photosynthesis, visible light has enough energy to:

excite electrons.

A specific region of DNA that contains the information to produce a complete protein is called a:

gene

ATP is produced in the mitochondria by a series of biochemical reactions. In what order do these reactions occur?

glycolysis; the citric acid cycle; the electron transport chain

How are open reading frames identified in a genome?

start and stop codons

You are told that a gene that codes for green hair can be found at position 3 on chromosome 6. You have been given the gene's:

locus

Which statement about glycolysis is false?

It requires oxygen.

Which choice regarding DNA replication is true?

Mistakes in DNA replication are a mechanism of evolutionary change.

How are new alleles formed?

Mutations cause changes to the DNA nucleotide sequence.

Which statement is false?

Only animal cells contain DNA; plant cells do not.

?

Passive transport, which is the movement of molecules from areas of high concentration to that of low concentration across the membrane, is usually coupled to processes that: B. establish a dynamic equilibrium with no net gain or loss in energy for the cell. E. does not require energy usage.

If one strand of a DNA molecule has the base sequence ATTGCAT, its complementary DNA strand would be:

TAACGTA

Photosystems are:

arrangements of light-catching pigments within chloroplasts.

Energy used in cellular respiration can originate from:

carbohydrates, proteins, and fats.

Which gas is used by plants to produce molecules that make up plant structures?

carbon dioxide

The inputs of cellular respiration are oxygen and sugar; the outputs of cellular respiration are:?

carbon dioxide, water, and ATP.

In transcription, a copy of ______________ is made. In translation, that copy is used to direct the production of a(n) _______________.

a protein's sequence of bases; amino acid

Each codon on a DNA strand codes for:

a single amino acid

Considering the principle of complementary base pairing, you would expect an equal ratio of which two nitrogenous bases in a DNA molecule?

adenine and thymine

Biologically speaking, a pigment is a:

molecule that absorbs a photon.

What exactly does transfer RNA (tRNA) transfer?

amino acids to the ribosome during translation

Eukaryotic mRNA processing, such as intron removal, occurs in the:

nucleus

A group of several genes, along with the elements that control their expression as a unit, are called a(n):

operon

Which by-product of photosynthesis was important in altering the atmosphere of the earth so that aerobic organisms could evolve?

oxygen

What are the outputs of the process of photosynthesis? A. ATP and sugar B. oxygen, water, and ATP C. ATP and water D. oxygen and sugar E. carbon dioxide, sugar, and water

oxygen and sugar

The color of a daisy's petals is a(n) ________, the instructions for which are found in a gene controlling petal color. There may be many alternate versions of this gene, which are called __________.

trait; alleles

To get from a gene to a protein, two steps must occur. What are those steps, in correct chronological order?

transcription and translation

What is the molecule that brings amino acids to the ribosome to be bound together during translation?

transfer RNA (tRNA)

A green plant can carry out photosynthesis if given nothing more than:

water, light, and air.

In E. coli, genes make up ______ of the DNA.

at least 90%

The first law of thermodynamics states that energy is constant; it can ____________________, but not _______________.

be transferred and transformed; created or destroyed

The molecules of the mitochondrial electron transport chain are located:

within in the inner membrane.

Beer, wine, and spirits are produced as the result of cellular metabolism by:

yeast occurring in the absence of oxygen.

chloroplast

The structure labeled "L" is a

cell wall

The structure labeled "M" is the:

The human genome is composed of approximately how many base pairs?

3 billion

What is the typical sequence of events in gene expression and protein synthesis?

DNA > RNA > protein

Why has DNA analysis been effective recently at overturning faulty criminal convictions?

DNA evidence is a more reliable individual identifier compared to eyewitness testimony.

engulfing of small photosynthetic prokaryotes by a larger cell.

According to the theory of endosymbiosis, the origin of chloroplasts probably involved:

a flagellum

Sperm cells are the only type of cell in animals that have:

Energy is released as ATP becomes ADP when ATP:

ejects one of its phosphate groups.

hypertonic.

If the solution surrounding a cell contains more solute than the cytoplasm inside the cell, the outside solution is said to be:

the smooth endoplasmic reticulum

In which organelle are lipids synthesized and modified within the eukaryotic cell?

Before an mRNA transcript exits the nucleus, ________ may be added and ________ removed. A. RNA polymerase; a cap and a tail B. a termination site; a promoter site C. a cap and a tail; introns D. introns; RNA polymerase E. DNA; RNA

? - not a or e try c

Describe the genetic material of a prokaryote.

Circular pieces of DNA are found in the cytoplasm.

The original source of electrons in the photosystems is:

H20

Which statement is true regarding the metabolic machinery of humans and animals?

Humans and animals can extract energy from sugars, lipids, and proteins.

partially permeable

Hydrophobic molecules can pass freely through the plasma membrane, but ions and polar molecules are impeded by the hydrophobic core. For this reason, plasma membranes can be considered:

hydrophillic

Phospholipids assemble spontaneously into bilayers driven by the attraction of their "tail" portions to each other and of their "head" portions to each other. The "head" portions are: A. hydrophobic. B. composed of carbon-hydrogen chains. C. directed away from intra- and extracellular fluid. D. hydrophilic. E. nonpolar.

Which statement best represents the relationship between respiration and photosynthesis?

Photosynthesis stores energy in complex organic molecules, whereas respiration releases it.

A cyclist rides her bike up a very steep hill. Which statement properly describes this example in energetic terms?

Potential energy in food is converted to kinetic energy as the cyclist's muscles push her up the hill.

nucleus

Prokaryotic cells lack:

Although the reactions of the Calvin cycle do not depend directly on light, they do not usually occur at night. Why? A. Plants must open their stomata to restore their water balance each night. B. It is usually too cold at night for these reactions to take place. C. The Calvin cycle depends on products of the light reactions that cannot occur at night. D. Carbon dioxide concentrations decrease at night. E. At night, plants have a negative water balance with the soil, due to reduced evaporation.

The Calvin cycle depends on products of the light reactions that cannot occur at night.

processes and packages proteins, lipids, and other molecules

The Golgi apparatus:

nucleus; bilayers

The ________ is the largest structure in eukaryotic cells. It is surrounded by a membrane structure that consists of two ________.

binding to beta-receptors, thereby preventing adrenaline from binding to the cell.

The chemicals in "beta-blocker" drugs reduce anxiety symptoms by:

The engulfed archaeon cells eventually became chloroplasts and mitochondria.

The endosymbiosis theory is often used to explain how chloroplasts and mitochondria came to contain their own, independent genetic material. Which statement is not part of the endosymbiosis theory?

A. to reduce membrane fluidity at higher temperatures.

The function of cholesterol in membranes is: A. to reduce membrane fluidity at higher temperatures. B. to increase membrane fluidity at higher temperatures. C. to increase membrane permeability at lower temperatures. D. to reduce membrane fluidity at lower temperatures. E. There is no function of cholesterol; it is tolerated in low amounts in mammalian cells.

Which of these occurs during transcription?

The information coded in DNA is copied into mRNA.

50

The lysosomes in a human cell contain approximately ________ types of digestive enzymes.

plant cell

The object pictured here: A. is an animal cell. B. is a nucleus. C. is a bacterial cell. D. could be either a plant or animal cell. E. is a plant cell.

active transport

The primary function of molecular membranes is the transport of ions and molecules in and out of cells. The movement of molecules from areas of low concentration to those of high concentration against chemical gradients is best described as:

ribosomes

The primary site of protein assembly within eukaryotic cells is the:

the vacuole

The structure labeled "N" is

nuclei

The structures labeled "A" are:

mitochondria

The structures labeled "D" are:

smooth endoplasmic reticula

The structures labeled "F" are

endocytosis

The transport of large molecules into the cell, across the membrane, is accomplished via:

E. It is the site of ribosome-subunit synthesis.

What is the main function of the nucleolus? A. It produces enzymes that are then exported to the lysosomes. B. It is the site of cellular waste digestion and recycling. C. It produces cell adhesion proteins that are then exported to the cell membrane. D. It is the site of photosynthesis in photosynthetic cells. E. It is the site of ribosome-subunit synthesis.

its covered with ribosomes

What makes the rough endoplasmic reticulum rough?

B. They are attached by gap junctions to remain in place.

Which of the following is not true of all cells? A. They arise from other living cells. - B. They are attached by gap junctions to remain in place. C. They assimilate nutrients. - D. They eliminate wastes. - E. They synthesize new cellular material. -

mitochondria and chloroplasts

Which of these are enclosed by a double membrane?

a nuclear membrane

Which of these is a cellular characteristic of all eukaryotes?

C. The rough endoplasmic reticulum is the site of much protein folding and packaging, whereas the smooth endoplasmic reticulum is the site of lipid synthesis.

Which of these is an important difference between the rough endoplasmic reticulum and the smooth endoplasmic reticulum? A. The smooth endoplasmic reticulum is the site of protein synthesis, folding, and packaging, whereas the rough endoplasmic reticulum is the site of lipid synthesis. B. The rough endoplasmic reticulum is the site of lipid synthesis, whereas the smooth endoplasmic reticulum is the site of digestion and recycling of cellular waste. C. The rough endoplasmic reticulum is the site of much protein folding and packaging, whereas the smooth endoplasmic reticulum is the site of lipid synthesis. D. The rough endoplasmic reticulum is covered in cilia, whereas the smooth endoplasmic reticulum is not. E. The rough endoplasmic reticulum is studded with chloroplasts, whereas the smooth endoplasmic reticulum is not.

lysosome

Which organelle is responsible for degrading waste within the cell?

osmosis deals only with water

Which statement best summarizes the differences between osmosis and diffusion?

They contain cytoplasm but never a plasma membrane.

Which statement is false regarding prokaryotic cells?

hypertonic

You are bored at a lunch meeting and surreptitiously place a raisin in your glass of water. The raisin swells to twice its original size. Relative to the water, the raisin must have been:

Chlorophyll's most important role during photosynthesis is:

converting light energy from the sun into chemical energy.

The complementary base pairs in a DNA molecule are stabilized by:

hydrogen bonds

The area within a gene that is not translated into protein is called a(n):

intron

Chemical energy:

is a form of potential energy stored in bonds between molecules.

During fermentation, yeast cells convert pyruvate to ethanol and CO 2. Fermentation also occurs in human muscle cells when oxygen is depleted. In the case of muscle cells, what are the by-product(s) of the fermentation of pyruvate?

lactic acid

Life gains most of its energy from:

sunlight

What are the inputs to the process of photosynthesis?

sunlight, water, and carbon dioxide

DNA is a macromolecule that stores information. Which component of the DNA is the source of this information?

the base

What is the primary site of protein assembly within eukaryotic cells?

the ribosomes

One of the four nucleotide bases in DNA is replaced by a different base in RNA. Which base is it, and what is it replaced by?

thymine, replaced by uracil