All of the Concept Checks

Darwin proposed the theory of evolution through the process of natural selection. Darwin used the term natural selection to mean

some heritable traits of a population are selected for (or against) by environmental conditions.

The fluidity in membranes is due to which molecule(s)?

lipids

Which is an example of bioinformatics?

mapping the rice genome

Which problem could, in theory, be solved by human gene therapy?

sickle-cell disease

You have discovered a new kind of cell with a strange new organelle that contains a highly hydrophobic compartment. Which will mostly certainly be abundant in this organelle?

Lipids

If you found a cell dividing, and you found that its daughter cells were haploid, you would have been observing

Meiosis II

If you were designing a space station to produce its own food by shining LED lights onto plants, which LED color could be omitted from the space station?

Yellow

Examine this micrograph of an onion root tip. The outlined cells are in mitosis. Which list correctly identifies the mitotic phases for the outlined cells?

a: metaphase, b: anaphase, c: telophase, d: prophase

This diagram represents osmosis of water across a semipermeable membrane. The U tube on the right shows the results of the osmosis. What could you do to level the solutions in the two sides of the right-hand U tube?

add more solute to the left-hand side

The image on the right is the summary equation for the process of photosynthesis. This reaction

builds food for the organism.

Which of the following cells would likely express the genes that code for hemoglobin?a) nerve cell b) white blood cell c)pancreas cell d)a.-c. e) None of the answer choices is correct.

e

Which would be more abundant in a muscle cell immediately after exercise? a) ATP b) ADP c)phosphate d)a. and c. e) b. and c.

e

The ability of an atom to chemically react mostly depends on the number of

electrons in the outer electron shell of the atom.

Cancers take a long time to develop because:

multiple DNA mutations must accumulate in the same cell for it to become cancerous.

Which of the following cells would likely express the genes that code for insulin?

pancreas cell

In order to transform the _______ of ATP into _______ available to do work, the bonds of ATP must be broken into ADP and an available phosphate group.

potential energy; kinetic energy

It was through Watson, Crick, Wilkins, and Franklin's discovery of DNA structure that they and other scientists were able to develop a deeper understanding of

the function of DNA in living organisms.

A person with lactose intolerance will suffer from digestive discomfort if milk products are consumed. This occurs because

the lactose molecules are not being hydrolyzed.

Water molecules form hydrogen bonds because

the water molecule forms a tetrahedron.

Oxygen as O2 is required for aerobic cellular respiration. The function of O2 in this process is

to accept the spent electrons at the end of the electron transport chain.

What is the process of putting genes from one organism into another organism?

transgenics

If a mutation prevents an mRNA from leaving the nucleus, what will not happen?

translation

The below figure shows the different processes of cellular respiration. Which correctly identifies the different processes?

1. glycolysis, 2. citric acid cycle, 3. electron transport

Fat molecules store 9 kcal per gram. There are about 454 grams in a pound of fat, so one pound of fat stores about 4,000 kcal of energy. If running at a moderate pace for one hour burns about 800 kcal of energy, how many hours must a person run to burn the energy stored in one pound of fat?

5 hours

What is the difference between mitosis and meiosis?

A single cell divides into two cells in mitosis but into four cells in meiosis.

When an electron is passed from the primary electron acceptor in the first photosystem to the second photosystem, it travels through an electron transport chain. What is produced as the electron travels through this electron transport chain?

ATP

Some prokaryotic and all eukaryotic cells use oxygen to harvest energy from food molecules. In what form is that harvested energy available to power cell work?

ATP molecules

What will happen to the process of aerobic cellular respiration if no O2 is available in the cell?

Aerobic cellular respiration will stop.

When a photon of the correct energy is absorbed by a photosystem, an electron is energized and transferred to a primary electron acceptor. How is the missing electron replaced?

An electron from hydrogen made available by splitting water replaces the missing electron

How can an antibiotic target infecting bacterial cells but not the human cells of a patient's body?

Antibiotic medicines target structures, such as cell walls, that bacteria have but human cells do not.

This is the general equation for photosynthesis—the process of capturing energy from sunlight and converting it to stored chemical energy. Which are the reactants?

CO2 and H2O

Earth's oceans are immense. Small floating organisms in the oceans, called phytoplankton, perform photosynthesis. If oceanic photosynthesis were to increase, what should happen to global CO2 levels?

CO2 levels should go down.

An organism's genetic information is stored within the sequence of _______. This information is transcribed into a sequence of _______, which are then translated into a sequence of _______.

DNA bases; RNA bases; amino acids

PCR, or polymerase chain reaction, amplifies target DNA fragments. This technique takes place outside of a cell and uses heat to separate the double-stranded DNA along with what?

DNA polymerase isolated from Archaea from hot springs

What could be produced by hydrolysis of a large carbohydrate molecule?

Disaccharide

In what way might a mutation in a proto-oncogene lead to cancer?

Dont know a)A mutation within the gene leads to an oncogene, which is more efficient at stimulating cell growth. b)A mutation creates multiple copies of the gene, which all together produce more growth-stimulating proteins. c)A mutation causes increased transcription at the gene, which then produces more growth-stimulating proteins. d)All of the answer choices are correct.

Because the p53 gene produces a protein that keeps cell metabolism and cell division in check, a cell that doesn't produce a functional form of this protein will

Dont know a)increase transcription and translation of the p53 protein. b)grow more slowly, stunting the tissue it occupies. c)divide rapidly, producing more cells with the same version of p53. d)cease cell division, not replacing old worn-out cells in the tissue.

The cells of your body contain a tumor-suppressing gene called p53. This gene produces a protein that keeps cell metabolism and cell division in check. The gene p53 can be inactivated by a DNA mutation that

Dont know a)makes multiple copies of p53. b)changes the shape of the protein to a nonfunctioning form. c)moves the p53 gene position to a location where more transcription occurs. d)ceases cell division.

You have discovered a new cell and see that it has a Golgi apparatus. It could be a member of

Eukarya

The term "DNA fingerprint" implies that an individual's DNA differs from the DNA of others just as fingerprints vary. How is a person's DNA unique?

Everyone has a different number of short tandem repeats.

If you were using a light meter beneath a canopy of leaves, which color would you detect most?

Green

The three domains of life are Bacteria, Archaea, and Eukarya. What is the principal difference between eukaryotes (Eukarya) and prokaryotes (Archaea and Bacteria)?

In eukaryotes, the interior of the cell is divided by internal membranes into specialized compartments.

A friend excitedly tells you of having inserted the sequence of the green fluorescent protein into an intron from a milk protein gene, planning to get rich by selling glow-in-the-dark milk. What should you say?

It won't work since introns are not expressed.

If a cell is unable to perform aerobic cellular respiration, what will then happen?

No ATP will be produced, causing all energy-requiring cell functions to cease.

Diurnal temperature variation describes the difference between a location's daytime high temperature and nighttime low temperature. Given how water moderates temperature, which location would have the greatest diurnal temperature variation?

Phoenix, Arizona, with an average humidity of 37%

One of the products of the citric acid cycle is CO2. This molecule is considered a waste molecule, since organisms performing aerobic cellular respiration will release it into the atmosphere. What reactant provided the carbon atoms used to produce this CO2?

Pyruvic Acid

A cell's cytoskeleton is a network of protein fibers that help a cell keep its shape. What other important function does the cytoskeleton serve?

The cytoskeleton guides organelles that must move from place to place within the cell.

The figure shows an overview of the different entry pathways to cellular respiration for different macromolecules. Why are none of the digestive products entering the electron transport chain directly?

The electron transport chain only receives electrons carried by reduced electron carrier molecules such as NADH.

Both cellular respiration and photosynthesis rely on electron transport chains embedded in membranes to produce ATP molecules. Which correctly describes the difference between the two types of electron transport chains?

The final electron acceptor in cellular respiration is water, while the final electron acceptor in photosynthesis is molecular oxygen.

When proteins are heated, they usually denature. If this molecule of DNA were heated, what part would break apart first?

The nitrogen base pairs would separate in the interior of the molecule.

Sometimes a DNA mutation changes which nucleotide sits at a given position in a gene. How can this still result in a protein that is constructed correctly?

The nucleotide substitution creates a "new" codon that calls for the same amino acid as the "old" codon.

The cell is sometimes described as a protein factory. If that is true, which accurately describes the functions of the endomembrane system?

The ribosomes on the rough endoplasmic reticulum are analogous to a production line in a factory.

Enzymes catalyze the many reactions in a cell. There are hundreds of different enzymes in a cell—each with a unique three-dimensional shape. Why do cells have so many different enzymes?

The shape of the enzyme's active site generally fits a specific substrate.

This graph illustrates how an enzyme catalyzes reactions in biological systems. To start a reaction, a certain amount of energy must be absorbed by the reactants. This is called the energy of activation. Which of the following is the normal energy of activation?

a

You are observing a colony of fruit flies and notice one genetic line stops making wings. This is probably due to a mutation in

a homeotic gene.

You are given a sample taken from a living organism but are not told what kind of organism, only that it was denied oxygen in the container which held it. If you did a biochemical analysis, what would most likely be present in a sample of this organism?

a) NAD+ b) alcohol c)oxygen d)lactic acid e) b) or d)

Within all living organisms, a series of chemical reactions known as metabolism allows these organisms to

a) convert energy from one form to another. b) recycle matter from one form to another. c) both and b

Which property or properties of water are critical for life?

a) decreased density when floating b) cohesion c)hydrogen bonding d) all correct

What contributes to variation in offspring in sexually reproducing organisms?

a) independent orientation of tetrads during meiosis b) crossing over of homologous chromosomes during tetrad formation c)sexual reproduction d) All of the choices are correct.

Consider the radioactive isotope fluorine-18. Fluorine-18 differs from fluorine-19 in

a) its atomic mass. b) the number of neutrons found in the nucleus. c)the stability of its nucleus. d)all of the above.

Not all science discoveries are based on experiments. Which would be best described as science based on exploration?

a) sequencing the human genome b) describing a new bird species from the Philippines c)a project to find preserved specimens of the probably extinct Rocky Mountain locust frozen in glaciers d)all of the above

If you were observing a cell during mitosis and you saw that there were chromosomes lined up in the center of the cell, you would be looking at

metaphase

In what way can a cell control activation of genes in the nucleus?

regions of DNA that are tightly packed inhibit RNA polymerase.

At the molecular level, genetic material must account for three important properties of inheritance. The genetic material must •be able to copy itself. •be able to direct the expression of an organism's phenotype. •generate variation in some manner. Which process accounts for each of these properties?

replication translation mutation

If you found an RNA floating in the cytoplasm of a cell connected to one amino acid, you would have found what kind of RNA?

tRNA