Microbiology-Exam 2

Microbes grow and produce quickly at these temp

40-140

Plasmids are self replicating circular molecules of DNA caring genes that are essential to cell survival

FALSE

The infectious dose for a pathogen remains constant regardless of the host's health and age

FALSE

all mutagens cause cancer

FALSE

fermentation requires oxygen

FALSE

Why are the terms gene expression and protein synthesis often used interchangeably?

Gene expression requires transcription and translation, which is protein synthesis;

How is a ribonucleotide different from a deoxyribonucleotide?

Ribonucleotides contain ribose instead of deoxyribose, which is found in deoxyribonucleotides. Ribonucleotides are used to build RNA, while deoxyribonucleotides are used to build DNA. Ribonucleotides will not incorporate thymine as a nitrogen base and instead use uracil;

Clinical Aspects of Viruses and Prions: Detection tests are evaluated based on specificity, sensitivity, and have a short turnaround time.

Specificity means that the diagnostic test reliably detects only the virus(es) of interest without producing false positive results. Sensitivity means the test detects very low levels of the target to limit false negative results.

Any Step in a viral replication pathway can be a drug target

TRUE

Phage bacteria conversion can make the bacteria more virulent

TRUE

The products resulting from fermentation depends on the enzymes the microorganism has

TRUE

Transduction is the process in which DNA is passed from one bacterium to another through a bacteriophage

TRUE

pH decreases as fermentation proceeds

TRUE

Why don't bacteriophages have the animal virus life cycle stage of "uncoating"?

Uncoating is characterized by the release of the genome from the capsid after the virion enters the cell. Bacteriophages do not enter the host cell but inject the genome from outside the cell.

Which of the following are characteristics of the Kingdom Fungi? (Select all that apply.) a. They have a cell wall. b. They are mainly unicellular. c. They are mostly pathogens. d. They contain peptidoglycan in their cell wall. e. Some are photosynthetic. f. They lack mitochondria. g. They are prokaryotic and eukaryotic.

a

Which of the below include eukaryotic cells? (Select all that apply.) a. Fungi b. Yeasts c. Protista d. Bacteria e. Helminths f. Animalia g. Archaea h. Plantae

a, b, c, e, f, h;

In Griffith's classical experiments on transformation, which of the following scenarios led to a dead mouse? Choose all that apply. a. Infecting the mouse with a living strain of S. pneumoniae that makes a capsule b. Infecting the mouse with a heat-killed strain of S. pneumoniae that makes a capsule c. Infecting the mouse with a heat-killed strain of S. pneumoniae that makes a capsule and a living strain of S. pneumoniae that cannot make a capsule d. Infecting the mouse with a living strain of S. pneumoniae that cannot make a capsule

a, c;

The presence of which of the following would be helpful in distinguishing a prokaryote from a eukaryote? (Select all that apply.) a. Peptidoglycan b. Phospholipids c. A cell wall d. A nucleus e. Chloroplasts f. Ribosomes g. Ability to carry out active transport h. DNA

a, d, e;

Which of the following are not characteristics of eukaryotes? (Select all that apply.) a. They are generally simpler than prokaryotes. b. They can be multicellular. c. They all have a nucleus. d. They tend to have multiple chromosomes. e. They can have a cell wall. f. They include pathogens. g. They divide by mitosis. h. They make up the Domain Archaea. i. They make up the Domain Bacteria. j. They make up the Domain Eukarya.

a, h, i;

Indicate the true statements about eukaryotic cells and then reword the false statements so that they are true. a. Eukaryotic cells have 70S ribosomes on the rough endoplasmic reticulum. b. Eukaryotic cells sexually reproduce by mitosis. c. Eukaryotic cells can make up unicellular or multicellular organisms. d. Eukaryotic cells always have a cell wall. e. Eukaryotic cells can be photosynthetic. f. Eukaryotic cells use fimbriae for motility g. Yeast is a multicellular eukaryote

a. False. Eukaryotic cells have 80S ribosomes OR Prokaryotic cells have 70S ribosomes, b. False. Eukaryotic cells asexually reproduce by mitosis OR Eukaryotic cells sexually reproduce by meiosis, c. True, d. False. Eukaryotic cells sometimes have a cell wall, e. True, f. False. Eukaryotic cells use flagella, cilia, or pseudopods for motility (they do not make fimbriae). (Note: A student may name any eukaryotic motility structure, or all of the motility structures, discussed in the chapter to correct the statement.) g. False. Yeast is a unicellular eukaryote;

Does the statement apply to DNA, RNA, or both? a. Contains uracil b. Usually double stranded c. Found in the cytoplasm of eukaryotic cells d. Contains thymine e. Is made by transcription f. Contains adenine g. Made of nucleotides h. Contains ribose i. Contains phosphodiester bonds j. Built in a 5' to 3' direction

a. RNA, b. DNA, c. RNA, d. DNA, e. RNA, f. DNA and RNA, g. DNA and RNA, h. RNA, i. DNA and RNA, j. DNA and RNA;

Which of the following is produced by transcription? a. mRNA b. Protein c. DNA d. None of the above

a;

Which of the following characteristics regarding eukaryotic organelles supports the endosymbiotic theory? (Select all that apply.) a. Eukaryotic ribosomes are 70S just like prokaryotic ribosomes. b. Mitochondria and chloroplasts have 70S ribosomes like prokaryotes. c. Mitochondria and chloroplasts are double-membrane organelles similar in size to bacteria. d. Mitochondria and chloroplasts have their own circular chromosome. e. Eukaryotes can have cell walls like prokaryotes.

b, c, d;

Quorum sensing helps cells____________. a. mutate b. form biofilms c. carry out transduction d. copy their DNA e. perform conjugation

b;

Cells that can be transformed are said to be _____________.

competent;

What would cause a cell to have more mitochondria

energy commands

____________is an exportation process used in eukaryotes and involves vesicles that may bud off the Golgi apparatus. In contrast, _____________ is an importation process by which a solid or a dissolved substance enters the cell by being engulfed by invaginations of the plasma membrane.

exocytosis, endocytosis

2 strands of DNA are held together by

hydrogen bonds

Cells that are active and have high energy have more

mitochondria

Not used to perform viral diagnostic test

molecular methods to identify viral metabolic by products

A________ is a change in the nitrogenous base

mutation

_________________is also called cell drinking and is an example of an endocytic process.

pinocytosis

misfoled proteins that cause neurons to die

prions