BISC 160 Exam 1

What type of bond is formed if one atom is more electronegative than the other atom? A-van der Waals B-hydrogen C-nonpolar covalent D-covalent E-polar covalent

E

Which is a benefit of sexual reproduction over asexual reproduction? A-Evolution will occur at a slower rate when there are two parents B-There is less variation from generation to generation C-The offspring are all identical to the parents D-More offspring can be produced E-The interaction of the genes from both parents bring about genetic variation

E

The outer membrane of the nuclear envelope is continuous with the membrane of the ______ and is usually covered with attached ribosomes A-cell wall B-endoplasmic reticulum C-chromatin D-nucleolus E-plasma membrane

B

Which statement concerning a scientific theory is false? A-It is supported by many observations B-It is unchangeable C-It is based on a number of hypotheses D-It may suggest practical applications

B

An organism that reproduces _______ produces genetically variable offspring. A-asexually B-by fragmentation C-sexually D-by cloning

C

When a small amount of hydrochloric acid (HCl) is added to a solution of Na2HPO4, the pH of the solution does not change markedly. The pH also does not change drastically when a small amount of sodium hydroxide (NaOH) is added to this same solution. Based on these observations, the compound Na2HPO4 is: A-acting as a solvent B-able to donate hydrogen atoms to HCl C-acting as a buffer D-able to remove hydrogen ions from the OH- of NaOH E-an enzyme facilitating the reaction between HCl and NaOH

C

Which substance correctly identifies as reactant in the following chemical equation? CO2 + H2O <--> H2CO3 A-water B-oxygen C-hydrogen D-carbonic acid E-carbon

A

Plants lack organ systems for disposing of toxic metabolic waste products. Their cells' vacuoles are like what animal cell organelle? A-nucleolus B-chloroplasts C-endoplasmic reticulum D-lysosomes E-mitochondria

D

Which functional group forms bridges to help stabilize a protein's quaternary structure? A-phosphate B-amino C-hydroxyl D-sulfhydryl E-carbonyl

D

The location and/or metabolism of a substance such as a hormone or drug can be followed in the body by labeling the substance with a(n) ________ A-radio isotope B-DNA molecule C-acid D-isotope E-element

A

If tyrosine and isoleucine, two amino acids, undergo condensation, where does the new bond form? A-between carbon of the carboxyl group and the hydrogen of the R group B-between carbon of the carboxyl group and the nitrogen of the amino group C-between carbon of the R group and the nitrogen of the amino group D-between oxygen of the R group and hydrogen of the amino group E-between carbon of the carboxyl group and hydrogen of the amino group

B

The primary purpose of homeostasis is to: A-convert an organism to live in a harmful environment B-maintain a constant internal environment C-accept responses to stimuli D-allow unrestricted movement of an organism E-provide unlimited growth within an organism

B

What are the units of hereditary information? A-RNA B-genes C-hormones D-proteins E-nucleotides

B

What statement best describes biology? A-the study of how organisms are related to one another B-the science of life C-the measurement of population D-the naming of organisms E-the study of natural selection

B

What differentiates an organic compound from an inorganic compound? A-an organic compound lacks isotopes B-an organic compound lacks valance electrons C-an organic compound contains 2 or more atoms D-an organic compound is basic rather than acidic E-an organic compound contains 2 or more carbon atoms

E

What large molecules are essential in determining the structure and function of cells and tissues? A-genes B-RNA C-hormones D-nucleotides E-proteins

E

Which is a key component of a cytoskeleton? A-centrosome B-endoplasmic reticulum C-ribosomes D-DNA E-microtubules

E

Which organelle can be considered a sorting, processing, and packaging center? A-centriole B-centrosome C-vacuole D-endoplasmic reticulum E-golgi complex

E

Which statement best describes cell theory? A-All living organisms can move from 1 place to another to find food or to escape predators B-All living organisms can form a population that is able to adapt to the enviornment C-All living organisms respond to stimuli D-All living organisms grow and develop E-All living organisms are composed of basic units called cells

E

Which strategy is most effective for larger cells to have an effective surface area to volume ratio? A-locomotion B-being short and fat C-having thinner plasma membrane D-having a completely spherical shape E-having thin, finger-like projections

E

All of the members of the same species occupying the same area at the same time constitute a(n): A-population B-biosphere C-ecosystem D-individual E-community

A

For the following medical condition which of the following is likely the cellular organelle or structure that has been affected in such a way as to cause a condition? The sperm of a man cannot swim, thus rendering him infertile. A-mitochondria B-chloroplasts C-nucleus D-peroxisome E-lysosome

A

How can we identify a particular element? A-by its number of protons B-by its around of energy levels C-by its number of electrons D-by its shape of valance shells E-by its number of neutrons

A

Intermediate filaments are most closely associated with which of the following? A-keratins B-myosin C-microvilli D-psuedopodia E-actin

A

What represents the most basic level of chemical organization? A-atom B-tissue C-cell D-molecule E-organism

A

Which statement best summarizes the difference between DNA and RNA? A-DNA comprises the genes, while RNA is a direct participant in the process of protein synthesis B-DNA is the primary energy currency of the cell C-DNA is a polymer and RNA is a monomer D-RNA is a protein and DNA is a nucleic acid E-RNA is a single strand form of DNA

A

Why is it advantageous for cells to be small? A-A small cell has a small volume relative to surface area, thereby increasing efficient transport B-A small cell size prevents a cell form weighing too much C-A small cell size occupies less space in nature where space is limited D-A small cell has a small surface area relative to volume, thereby facilitating ion balance. E-A small cell is better able to conserve energy than a larger cell

A

You place equal numbers of dark and light varieties of feeder crickets into a terrarium containing a species of lizard. After 2 days, you notice the dark variety of the crickets was less common than the light variety. What process is taking place on the small scale within the terrarium? A-natural selection B-speciation C-reproduction D-evolution

A

A molecule of a saturated triacylglycerol contains: A-the minimum number of double bonds with carbons in the fatty acid chains B-the maximum number of hydrogen atoms in the fatty acid chains C-alternating single and double bonds between carbons in the fatty acid chains D-the maximum number of triple bonds between carbons in the fatty acid chains E-fatty acid chains with both amino and carboxyl group

B

An atom X contains 14 protons, 13 electrons, and 12 neutrons, and atom Y contains 14 protons, 14 electrons, and 12 neutrons. What can you conclude A-X and Y are isotope of the same element B-X and Y are atoms of the same element C-X and Y are both ions D-Y is an ion but X is not E-X and Y both have filled valance shells

B

Which is a property of unsaturated fats? A-they contain more hydrogen than do saturated fats having the same number of carbon atoms B-they are generally liquid at room temperature C-they have fewer fatty acids per fat molecule than do saturated fats D-they have no double bonds in the carbon chains of their fatty acids E-they are more common in animals

B

If a toxin, such as a bacterial toxin, destroys ribosomes, what cellular activity will be affected first? A-movement B-active transport C-protein synthesis D-energy storage E-DNA synthesis

C

In living organisms, chemical reactions responsible for growth, repair, and nutrition are collectively referred to as: A-homeostasis B-genetics C-metabolism D-development E-adaptation

C

Isotopes differ from each other with respect to the number of: A-electrons only B-protons only C-neutrons only D-both protons and electrons

C

Nitrogen has 5 electrons in its valance shell. How many electrons does it need to complete its valance shell? A-7 B-1 C-3 D-2 E-8

C

On a scientific expedition into new territory you discover a previously undescribed organism living within the very hot environment of a geyser. The organism has a cell well composed of pseudopeptidoglycan, is single celled, heterotrophic, and has no true nucleus. In what domain would you most likely place this organism? A-bacteria B-eukarya C-archea D-not enough information to tell

C

The existence of a separate set of ribosomes and ______ in mitochondria and chloroplasts provide support for serial ______. A-golgi; endosymbiosis B-rough endoplasmic reticulum; endosymbiosis C-DNA; endosymbiosis D-DNA; evolution E-none of the above

C

The smooth ER is the primary site for synthesis of phospholipids and cholesterol needed to make_____ A-hormones B-ATP C-cell membrane D-DNA E-ribosomes

C

Which description illustrates the tertiary structure of a protein molecule? A-bonding of two amino acids to form dipeptide B-association of several polypeptide chains by weak bonds C-three-dimensional shape of an individual polypeptide chain D-order in which amino acids are joined in a peptide chain E-folding of a peptide chain to form an alpha helix

C

A base is defined as a(n) ________ acceptor. A-neutron B-cation C-anion D-proton E-electron

D

What two organelles are both responsible for converting energy into forms that can be used by cells? A-lysosomes and chloroplasts B-mitochondria and lysosomes C-ribosomes and chloroplasts D-mitochondria and chloroplasts E-mitochondria and peroxisomes

D

Which pair matches the correct macromolecule with the bond that joins subunits? A-tiracylglycerol-glycosidic linkage B-polysaccharide-peptide bond C-protein-ester linkage D-nucleic acid-phosphodiester linkage E-steroid-peptide bond

D

Why can table salt (NaCl) dissolve easily in water? A-water can add electrons to the sodium ion B-water is polar and salt is non polar. Non polar compounds are more soluble in polar solvents because they are able to form strong covalent bonds that result in a breaking up of the molecule being dissolved C-water can form covalent linkages with salt molecules D-The partial positive charge of the hydrogens in the water molecule can associate with the negative charge of the chlorine, and the partial negative charge of the oxygen of the water molecule can associate with the positive charge of the sodium ion. E-water can remove electrons from the chloride ion, which causes the latter to dissociate from the sodium and dissolve.

D