Bio 110 Exam 1

Which of these statements is true? A. HDL is "good cholesterol" because it contains more protein than lipid, so will pick up excess cholesterol in the body. B. LDL is "good cholesterol" because it is light (low density) so does not accumulate in arteries. C. HDL is "bad cholesterol" because it is heavy (high density) so accumulates in the arteries, causing plaques. D. LDL is "bad cholesterol" because it contains less protein than lipid and will deposit extra cholesterol in the arteries. E. Both A and D are true

E

Uses oxygen if present, but can survive without it

Facultative aerobe

1) High in peptidoglycan 2) retains colored stain (purple)

Gram +

1) Low in peptidoglycan 2) loses colored stain 3) complex outer membrane of lipopolysaccharides (endotoxins)

Gram -

A mutation that caused a polar amino acid substitution in a protein instead of a nonpolar amino acid would cause the protein to: A. be more hydrophilic. B. be longer. C. be more hydrophobic. D. have more carboxylic acids

A

During digestion, various enzymes are secreted into your digestive tract to break down macromolecules. This process: A. requires water molecules. B. releases water molecules.

A

Some patients with Parkinson's disease have a more uncommon genotype at the ACT gene. They are homozygous for a form of that protein in which there is an alanine at position 15 rather than a threonine. This substitution results in a protein that is: A. less hydrophilic. B. longer. C. less hydrophobic. D. shorter.

A

The Earth's early atmosphere was ______________. This changed when some bacteria evolved the ability to __________, which releases oxygen A. anaerobic / photosynthesize B. aerobic / photosynthesize C. anaerobic / ferment D. aerobic / ferment

A

1) lipid cell wall 2) introns 3) extremophiles 4) lack nucleus

Archea

True or False. Bacterial conjugation is a form of sex. A. True because all forms of sex, including conjugation, produce new individuals. B. True because all forms of sex, including conjugation, create a new combination of genetic material. C. False because single-celled organisms cannot have sex. D. False because bacteria are not male and female.

B

When water vaporizes, which bonds are broken? A. The covalent bonds between the hydrogens and oxygen within a water molecule. B.The hydrogen bonds between water molecules C. The covalent bonds between water molecules D. The hydrogen bonds between the hydrogens and oxygen within a water molecule.

B

Which of the following is a plausible hypothesis for why Bacillus subtilis living on the south-facing slopes of the Evolution Canyon have more efficient biosynthesis than those living on the north-facing slopes? A. The bacteria are from different species and are expected to have different biosynthetic abilities. B. The south-facing slopes are a more extreme environment and efficient biosynthesis is an adaptation to this environment. C. The south-facing slope has more resources available for growth so the bacteria have more energy to biosynthesize at a greater rate. D. The south-facing slope is the more desirable habitat and the bacteria with greater biosynthetic ability outcompeted the others for this habitat.

B

1) peptidoglycan cell wall 2) exons 3) lack nucleus

Bacteria

A colony of antibiotic-resistant bacteria is mixed with a colony of antibiotic-sensitive bacteria. After a few days grown in the presence of antibiotics, all of the bacteria are resistant to the antibiotic. Which of these is most likely to result in this rapid spread of resistance in a bacterial population? A. Transduction B. Transformation C. Conjugation D. Binary fission

C

Bacteria show many types of symbiotic relationships with other organisms. Which of the following is NOT a mutualistic relationship between bacteria and another organism? A. Cellulose digesting bacteria living in the digestive tract of termites. B. The bacterium Bacteroides thetaiotaomicron living in an intact human intestine. C. The bacterium that causes the plant disease leaf spot on a Dieffenbachia plant. D. Bacteria that synthesize vitamins living in the human digestive tract.

C

Ezetimibe lowers LDL cholesterol by: A. Blocking the production of cholesterol in the liver. B. Binding to bile acids in the intestine, preventing them from being absorbed and causing the liver to produce more bile. C. Blocking a sterol transporter, reducing uptake of cholesterol in the intestine. D. Inhibiting an enzyme that controls the rate of cholesterol production in the body.

C

Lard is solid at room temperature, whereas fish oil is a liquid. You extract the fatty acid molecules from both of these fats and compare their chemical composition. Based just on your knowledge of their state at room temperature, you hypothesize that the fatty acids from the lard will contain __________ hydrogen atoms when compared to the fatty acids found in fish oil. A. fewer B. the same number of C. more D. You cannot determine this from the information provided

C

Which component of a water molecule is most electronegative? A. Both hydrogen atoms B. One hydrogen atom is more electronegative than the other C. The oxygen atom D. The oxygen atom and hydrogen atoms are equally electronegative.

C

Physical connection is used to pass a fertility plasmid to a partner

Conjugation

A researcher discovers a new species of bacteria that obtains its energy from other organisms and its carbon from the atmosphere. This species can be categorized based upon its mode of nutrition as a: A. chemoheterotroph. B. photoautotroph. C. photoheterotroph. D. chemoautotroph.

D

How old is the Earth? A. 5 million years old B. 600 million years old C. 3.5 billion years old D. 4.5 billion years old E. 13 billion years old

D

Nitrogen, a necessary element for the synthesis of amino acids and nucleic acids, makes up about 78% of the atmosphere. It is available to organisms through the process of nitrogen fixation carried out only by: A. fungi. B. plants. C. animals. D. bacteria. EAll of the above.

D

What determines the cohesiveness of water molecules? A. Hydrophobic interactions B. High specific heat C. Covalent bonds D. Hydrogen bonds E. Ionic bonds

D

Which level of protein organization describes the interaction of more than one polypeptide chain to make a functional protein? A. Primary. B. Secondary. C. Tertiary. D. Quaternary.

D

Which of these is not a function of cholesterol in your body? A. It is a precursor molecule for steroidal hormones like estrogen. B. It is a molecule found in cell membranes. C. It enables the body to make Vitamin D. D. It stores chemical bond energy that can be converted to ATP. E. It is used to make the bile acids that are produced for digestion.

D

Which of these statements is not true of the exotoxin produced by the bacterium Clostridium botulinum? A. It affects the human nervous system. B. It is used for botox cosmetic injections. C. It is produced only by endospores. D. It's effect is caused by the lippolysaccharides it produces D. It only forms endospores in anaerobic environments.

D

Must have oxygen to survive

Obligate aerobe

Can't thrive in presence of oxygen (some species die)

Obligate anaerobe

use of 3rd party viral phage to inject genetic information into a diff prokaryote

Transduction

Uptake of naked or loose DNA from environment

Transformation