Life Sciences Misc. (MS Science Bowl)

Which of the following materials is the STRONGEST in terms of tensile strength per mass:

• steel
•   a spider’s web
•   cotton fibers
•   nylon fibers

Which of the following is a property of carbon that makes it most effective as a polymer building block:

• it is in period 2 of the Periodic Table
•   it is a non-metal
•   it has a valence of 4
•   it is highly electronegative

Tags

NGSS.HS-LS1-6

NGSS.HS-PS1-1

Beeswax is BEST described as a:

• protein with small amounts of sugar
•   petroleum derivative
•   short-chain carbohydrate
•   long-chain hydrocarbon

Tags

NGSS.HS-LS1-6

Honey is considered hygroscopic because it:

• is very dense for a sugar
•   loses water to its environment
•   attracts water from the air
•   expands rapidly on heating

Which of the following is NOT one of the substituents attached to the asymmetric carbon of an amino acid?

• Carboxyl group
•   Carbonyl group
•   Amine group
•   Hydrogen atom

Tags

NGSS.HS-LS1-6

Infrared spectroscopy is used to help identify various chemical compounds. Each functional group is identified by a peak at a particular wavelength. If a scientist synthesizes a fatty acid in the lab, which of the following peaks would indicate that impurities were present?

• A peak indicating an amino group
•   A peak indicating a carboxylic acid –OH stretch
•   A peak indicating a carbon-carbon double bond
•   A peak indicating sp2-hybridized carbon-hydrogen bonds

Tags

NGSS.HS-PS4-4

Which of the following statements is true of microbial biofilms?

• Cells within the biofilm are encased within a layer of polysaccharide [pol-ee-SAK-uh-ryd]
•   Biofilms almost always consist of only a single bacterial species
•   Biofilms are restricted to freshwater environments
•   Biofilms typically are small because resources are unable to circulate through them

An environmental toxin introduced into a eukaryotic [yoo-KAR-ee-oh-tik] cell prevents the cell from producing ribosomes [RY-buh-sohms], yet DNA replication still occurs. From this information, which of the following enzymes is likely affected?

• DNA polymerase [POL-uh-muh-rays]
•   RNA polymerase
•   Helicase
•   Primase

The polymerase chain reaction (PCR) process is a method that makes it possible to replicate DNA segments in a very short amount of time using alternating periods of heating and cooling. The periods of heating would denature most proteins, such as DNA polymerases [pol-uh-muh-RAYS-uhs], and make them nonfunctional, especially at the high temperatures used during PCR. How is this obstacle overcome in modern PCR reactions?

• DNA polymerase is added between each period of heating and cooling
•   The DNA polymerase used is from a species of bacteria that live in hot springs, so the DNA polymerase can function at high temperatures
•   RNA polymerase is more heat resistant and is used instead, and then the DNA is reverse transcribed from the RNA
•   DNA polymerases in most species are proteins that do not denature easily, so this process can function at high temperatures

A segment of unlabeled DNA undergoes replication in a solution containing all necessary materials and in which the nitrogenous bases in the solution are radioactively labeled. Two complete, double-stranded DNA segments form. Following replication, which of the following is likely to be observed?

• One strand on each of the two DNA segments is radioactively labeled, while the other strand on each of the two segments is unlabeled
•   Both strands of one DNA segment are radioactively labeled, while both strands of the other segment are unlabeled
•   Both strands on each segment of DNA contain a mixture of radioactively labeled and unlabeled base pairs
•   Both segments of DNA have all their nitrogenous bases in both strands labeled

Tags

NGSS.HS-LS3-2