Bio chapter 16 hw q's

there are four bacteria in an egg salad that is left out at room temperature. After two hours, how many bacteria will be in the egg salad? A. 2048 B. 32 C. 256 D. 8

256- the bacteria would double 6 times in 2 hours, so the total number of bacteria in the egg salad would be 256

You are examining a fragment of material from an unknown life-form extracted from a sample taken deep in Earth's crust. which of the following clues would convince you the sample came from an archaeal cell? A. peptidoglycan in the cell wall material B. genes lacking introns C. histones associated with DNA and some introns present in genes, but no evidence of membrane-enclosed organelles. D. membrane-enclosed organelles

Histones associated with DNA and some introns present in genes, but no evidence of membrane-enclosed organelles

You are examining material from an unknown life-form extracted from a sample taken in the deep sea. Which of the following clues would convince you the sample came from the bacterial cell? A. membrane-enclosed organelles B. some genes lacking introns C. histones associated with DNA D. peptidoglycan in the cell wall material

Peptidoglycan in the cell wall material (this material is unique to bacterial cell walls)

What is the direct cause of gum disease? A. saliva in the mouth B. sugar in food C. food debris D. acids produced by bacteria E. plaque formed by bacteria

Plaque formed by bacteria

The bacteria initially persist in the predatory cell because: A. the predator knows the bacteria will be useful later on B. the predatory cell is unable to excrete them C. the predator was storing the bacteria temporarily, intending to digest them later D. the predatory cell is unable to digest the bacteria

The predatory cell is unable to digest the bacteria- this effect has been demonstrated in amoebas

T/F: bacteria reproduce by an asexual process in which one parent cell gives rise to identical daughter cells.

True- bacteria reproduce by binary fission, which is an asexual process in which one parent cell splits in 2 and give rise to identical daughter cells

The newly defined protist group SAR consists of __________. A. multicellular autotrophic algae B. unicellular heterotrophs and mixotrophs C. unicellular and multicellular autotrophic algae and unicellular heterotrophs and mixotrophs D. unicellular autotrophic algae

Unicellular and multicellular autotrophic algae and unicellular heterotrophs and mixotrophs

Which of the following organisms is a prokaryote? A. seaweed B. an amoeba C. a bacterium D. a slime mold

a bacterium

which structure helps bacteria to attach within the tissues that they will infect? A. cell wall B. flagella C. capsule D. nucleoid

Capsule- the gelatinous capsule that covers some bacteria helps them attach to the tissues that they will infect

According to this phylogenetic tree, which of these pairs of prokaryotic subgroups share the most recent common ancestor? A. Euryachaeota... cyanobacteria B. proteobacteria... crenarchaeota C. Proteobacteria... Euryachaeota D. Euryarchaeota... Crenarchaeota E. crenarchaeota... cyanobacteria

Euryarchaeota... Crenarchaeota

In the part of the cycle shown in tan, the chromosome number is _____

Haploid

Antibiotics exploit differences in structure between prokaryotes and eukaryotes in order to selectively attack pathogenic bacteria without affecting the human host. A key unique feature of bacteria that is targeted by antibiotics is __________. A. the presence of DNA and distinctive ribosomes B. the presence of mitochondria and endospores C. a cell wall containing peptidoglycan D. a cell wall containing peptidoglycans and endospores

a cell wall containing peptidoglycan (common target for antibiotics)

A microbe can be successfully cultured in the dark in a broth that indicates only sugar and a few amino acids. What type of metabolism does it have? A. a cyanobacterium B. a chemoheterotroph C. a photoautotroph D. a chemoautotroph

a chemoheterotroph (these organisms do not require light and use organic compounds for both energy and carbon)

The fantastic organism pictured below would surely qualify for a starring role in a horror film if it were a thousand times larger than it really is. In its active feeding stage, it is a single giant multinucleate cell that slides over moist organic matter, engulfing food particles as it grows. What is it? A. a plasmodial slime mold B. a fungus C. a macroamoeba D. a cellular slime mold

a plasmodial slime mold

What is the direct cause of demineralization of the enamel on teeth? A. acids produced by bacteria B. food debris C. saliva in the mouth D. plaque formed by bacteria E. sugar in food

acids produced by bacteria

Eukaryotes are most closely related to which of the following prokaryotic groups? A. bacteria B. protists C. Protozoa D. Archaea

archaea

_________ are organisms that live in extreme environments, such as hot springs. A. slime molds B. bacteria C. archaea D. protists

archaea

which of the following can increase your risk of atherosclerosis? A. avoiding a diet high in saturated fat B. avoiding high blood pressure C. avoiding sugary snacks D. avoiding exercise E. avoiding cigarettes

avoiding exercise

organisms that can cause nongonoccal urethritis are classified with _______. A. proteobacteria B. chlamydias C. spirochetes D. gram-positive bacteria E. cyanobacteria

chlamydias

After a long period of coevolution, the photosynthetic bacterium consumed by the predatory cell became the cellular organelle known as the: A. chloroplast B. nucleus C. centriole D. mitochondrion E. endoplasmic reticulum

chloroplast- carries out photosynthesis

A student finds some sea lettuce at the beach and wants to know if she is looking at the sporophyte or gametophyte stage. To find out she would need to ______. A. sequence an essential chloroplast gene B. examine the body form C. count the chromosomes within a cell undergoing mitosis D. determine if the body is multicellular

count the chromosomes within a cell undergoing mitosis- this would distinguish haploid and diploid forms, therefore the gametophyte and sporophyte stages

The prokaryotic cells that built stromatolites are classified as _________. A. proteobacteria B. chlamydias C. spirochetes D. gram-positive E. cyanobacteria

cyanobacteria

the prokaryotic cells that were the first to add significant quantities of oxygen to Earth's atmosphere are classified as ______ A. proteobacteria B. chlamydias C. spirochetes D. gram-positive bacteria E. cyanobacteria

cyanobacteria

What group of protsits is thought to be the main source of Earth's oil deposits? A. dinoflagellates B. amoebas C. brown algae D. diatoms

diatoms- thought to be the main source of oil, whereas coal was formed from primitive plants. Entrepreneurs eyeing the lipid droplets in diatoms and other algae as a renewable source of energy

why does the post-medieval skull in the video have such bad teeth? A. the skull is much older than the roman skull. B. the bacteria in people's mouths were becoming resistant to antibiotics. C. diets during this time period were high in sugar. D. people stopped brushing their teeth after the Roman period.

diets during this time period were high in sugar

A sign on the beach states, "Beach Closed. Red Tide." The organisms interfering with your use of this beach are probably _____. A. ciliates B. dinoflagellates C. diatoms D. amoebas

dinoflagellates

in the part of the cycle shown in blue, after the fusion of gametes, the chromosome number is ________

diploid

The bacterium Bacillus thuringiensis can withstand heat, dryness, and toxic chemicals that would kill most other bacteria. This indicates that it is probably able to form ___________. A. fimbriae B. endospores C. endotoxins D. pseudopodia

endospores- thick walled, extremely resistant structures produced by some gram-positive bacteria, including members of the genus bacillus

_________ evolved from _________ A. eukaryotes; prokaryotes B. eukaryotes; protists C. prokaryotes; eukaryotes D. unicellular algae; bacteria

eukaryotes; prokaryotes

Each multicellular alga shown at the top of the diagram is called a ________

gametophyte

Streptococcus aureus is classified with _________. A. proteobacteria B. chlamydias C. spirochetes D. gram-positive bacteria E. cyanobacteria

gram-positive bacteria

The important distinction between prokaryotes and eukaryotes is that prokaryotes _________ a nucles, whereas the cells of the eukaryotes ____ a nucleus A. lack; have B. shed; develop C. develop; shed D. have; lack

lack; have

spores are produced by the process of ____

meiosis

After a long period of coevolution, the aerobic bacterium consumed by the predatory cell became the cellular organelle known as the: A. endoplasmic reticulum B. mitochondrion C. centriole D. nucleus E. chloroplast

mitochondrion- they carry out aerobic respiration

Ancient cyanobacteria, found in fossil arrangements called stromatolites, were very important in the history of life because they ______. A. were probably the first living things to exist on earth B. were the first multicellular organisms C. are the oldest known archaea D. produced the oxygen gas in the atmosphere

produced the oxygen gas in the atmosphere -this produced a major change in the environment, making Earth hostile to anaerobic cells but enabling the evolution of cellular respiration, much larger cells, and eventually multicellular life.

By far the most abundant and widespread organisms on Earth are the ________. A. protozoans B. eukaryotes C. algae D. prokaryotes

prokaryotes

The chemoheterotroph Proteus vulgaris is a rod-shaped bacterium classified with ______. A. proteobacteria B. chlamydias C. spirochetes D. gram-positive bacteria E. cyanobacteria

proteobacteria

Which best describes the protist? A. protists are a monophyletic kingdom of very closely related species of unicellular eukaryotes B. protists are monophyletic kingdom of very closely related species of multicellular eukaryotes C. protists are diverse eukaryotes, typically unicellular, that do not fit into the plant, animal, or fungal kingdoms D. protists are early eukaryotes with very simple cells

protists are diverse eukaryotes, typically unicellular, that do not fit into plant, animal, or fungal kingdoms

Dentists sometimes give a patient antibiotics after a teeth-cleaning procedure, especially if the patient is older or has heart disease. What is the best explanation for this? A. antibiotics help kill the bacteria that move from the mouth to the bloodstream, and prevent the bacteria from contributing to atherosclerosis. B. the materials used during a teeth-cleaning procedure are high in low-density lipoproteins, and contribute to atherosclerosis. C. antibiotics help remove the plaque that remains on the teeth after a teeth cleaning procedure. D. teeth-cleaning procedures add bacteria to a person's mouth, and antibiotics are needed to control the bacteria

Antibiotics help kill the bacteria that move from the mouth to the bloodstream, and prevent the bacteria from contributing to atherosclerosis

Pea vines grow better and have better access to nitrogen if the seeds are coated with a fine black powder sold by nurseries. This powder might contain _____. A.bacteria to help the pea plants fix nitrogen B.antibiotics to prevent growth of disease-causing bacteria C.bacteria that will remove toxins from the surrounding soil D. nutrients to help pea plants grow

Bacteria to help the pea plants fix nitrogen -the inoculant contains nitrogen-fixing organisms. Endosymbiotic proteobacteria that live in root nodules of legumes, such as soybeans and peas, convert atmospheric nitrogen gas to a form usable by their host

You have been asked to participate in the cleanup of an old mining site. You build a treatment wetland to clean up a contaminated spring flowing out of the mine area. Before sending the water to the wetland, you pass it through a tank where Thiobacillus removes heavy metals. The plants and microbes of the wetland will absorb many of the contaminants that remain in the water. Your metho is an example of _________. A. bioremediation B. preservationism C. landscape ecology D. biodiversity maintenance

bioremediation (use of living organisms to detoxify pollutants)

people who produce very little saliva often have more cavities. what is the best explanation for this? A. people who produce very little saliva cannot support the growth of beneficial bacteria in their mouths. B. Since saliva normally helps neutralize acid and replace minerals on teeth, a lack of saliva leads to more cavities. C. a lack of saliva can make the brushing of teeth uncomfortable and reduce brushing leads to more cavities. D. people who produce very little saliva have trouble digesting proteins and fats, and tend to eat a diet high in sugar

since saliva normally helps neutralize acid and replace minerals on teeth, a lack of saliva leads to more cavities

spiral-shaped bacteria are likely to be placed with _______. A. proteobacteria B. chlamydias C. spirochetes D. gram-positive bacteria E. cyanobacteria

spirochetes

the multicellular alga shown at the bottom of the diagram is called a ______

sporophyte

which of the following is true? A. there is a correlation between periodontal disease and heart disease. B. heart disease causes periodontal disease C. periodontal disease causes heart disease D. heart disease is caused by the presence of bacteria in the blood

there is a correlation between periodontal disease and heart disease

________ has specially modified mitochondria that generate some energy anaerobically. Moreover, it causes an increasingly common and problematic sexually transmitted disease. A. dinoflagellates B. euglena C. trichomonas vaginalis D. paramecium

trichomonas vaginalis- Parabasalids such as trichomonas vaginalis are heterotrophs with modified mitochondria and can generate some energy anaerobically. Trichomonas vaginalis causes about 4 million new infections a year

Which of the following is the eukaryotic supergroup that contains fungi and animals? A. SAR B. excavata C. unikonta D. archaeplastida

unikonta- contains animals, fungi, and some protists