Concept explainers
Figure 30.15 Nutrient Cycling in Antarctic Lakes Is Performed Entirely by Microbes. Antarctic glacial lakes lack multicellular organisms, so all nutrient cycling is between various types of microbes, including bacteriophages. The surrounding environment provides some organic carbon.
List three major differences between this microbial loop and that found in the open ocean (figure 30.6).
Figure 30.6 The Microbial Loop. (a) Microorganisms play vital roles in ecosystems as primary producers, decomposers, and primary consumers. All organisms contribute to a common pool of dissolved organic matter (DOM) that is consumed by microbes. Viruses contribute DOM by lysing their hosts, and bacterial and archaeal cells are consumed by protists, which also consume other protists. These microbes are then consumed by herbivores that often select food items by size, thereby ingesting both heterotrophic and autotrophic microbes. Thus nutrient cycling is a complex system driven in large part by microbes. (b) Protists consume bacteria; in this case, a naked amoeba is consuming the cyanobacterium Synechococcus sp. which fluoresces red. (c) Protists consume protists; here, the ciliate Didinium sp. (rounded organism with two rows of cilia) is preying upon another ciliate, Paramecium sp.

Want to see the full answer?
Check out a sample textbook solution
Chapter 30 Solutions
PRESCOTT'S MICROBIOLOGY
- What is this?arrow_forwardMolecular Biology A-C components of the question are corresponding to attached image labeled 1. D component of the question is corresponding to attached image labeled 2. For a eukaryotic mRNA, the sequences is as follows where AUGrepresents the start codon, the yellow is the Kozak sequence and (XXX) just represents any codonfor an amino acid (no stop codons here). G-cap and polyA tail are not shown A. How long is the peptide produced?B. What is the function (a sentence) of the UAA highlighted in blue?C. If the sequence highlighted in blue were changed from UAA to UAG, how would that affecttranslation? D. (1) The sequence highlighted in yellow above is moved to a new position indicated below. Howwould that affect translation? (2) How long would be the protein produced from this new mRNA? Thank youarrow_forwardMolecular Biology Question Explain why the cell doesn’t need 61 tRNAs (one for each codon). Please help. Thank youarrow_forward
- Molecular Biology You discover a disease causing mutation (indicated by the arrow) that alters splicing of its mRNA. This mutation (a base substitution in the splicing sequence) eliminates a 3’ splice site resulting in the inclusion of the second intron (I2) in the final mRNA. We are going to pretend that this intron is short having only 15 nucleotides (most introns are much longer so this is just to make things simple) with the following sequence shown below in bold. The ( ) indicate the reading frames in the exons; the included intron 2 sequences are in bold. A. Would you expected this change to be harmful? ExplainB. If you were to do gene therapy to fix this problem, briefly explain what type of gene therapy youwould use to correct this. Please help. Thank youarrow_forwardMolecular Biology Question Please help. Thank you Explain what is meant by the term “defective virus.” Explain how a defective virus is able to replicate.arrow_forwardMolecular Biology Explain why changing the codon GGG to GGA should not be harmful. Please help . Thank youarrow_forward
- Stage Percent Time in Hours Interphase .60 14.4 Prophase .20 4.8 Metaphase .10 2.4 Anaphase .06 1.44 Telophase .03 .72 Cytukinesis .01 .24 Can you summarize the results in the chart and explain which phases are faster and why the slower ones are slow?arrow_forwardCan you circle a cell in the different stages of mitosis? 1.prophase 2.metaphase 3.anaphase 4.telophase 5.cytokinesisarrow_forwardWhich microbe does not live part of its lifecycle outside humans? A. Toxoplasma gondii B. Cytomegalovirus C. Francisella tularensis D. Plasmodium falciparum explain your answer thoroughly.arrow_forward
- Select all of the following that the ablation (knockout) or ectopoic expression (gain of function) of Hox can contribute to. Another set of wings in the fruit fly, duplication of fingernails, ectopic ears in mice, excess feathers in duck/quail chimeras, and homeosis of segment 2 to jaw in Hox2a mutantsarrow_forwardSelect all of the following that changes in the MC1R gene can lead to: Changes in spots/stripes in lizards, changes in coat coloration in mice, ectopic ear formation in Siberian hamsters, and red hair in humansarrow_forwardPleiotropic genes are genes that (blank) Cause a swapping of organs/structures, are the result of duplicated sets of chromosomes, never produce protein products, and have more than one purpose/functionarrow_forward
- Biology 2eBiologyISBN:9781947172517Author:Matthew Douglas, Jung Choi, Mary Ann ClarkPublisher:OpenStaxConcepts of BiologyBiologyISBN:9781938168116Author:Samantha Fowler, Rebecca Roush, James WisePublisher:OpenStax College
- Biology: The Dynamic Science (MindTap Course List)BiologyISBN:9781305389892Author:Peter J. Russell, Paul E. Hertz, Beverly McMillanPublisher:Cengage LearningBiology (MindTap Course List)BiologyISBN:9781337392938Author:Eldra Solomon, Charles Martin, Diana W. Martin, Linda R. BergPublisher:Cengage Learning




