During muscle contraction, the ______ of the sacromere becomes narrower.

A. A band
B. I band
C. M band
D. two of the above


Answer: B. I band

Biology & Microbiology

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Cyanobacteria

a) can fix nitrogen, thus causing many freshwater ecosystems to be limited by phosphorus availability. b) can mineralize phosphorus from wetland sediments, raising phosphorus levels in inland waters to the point of eutrophication. c) mineralize the phosphates in detergent from an organic corm into an inorganic form that can cause algal blooms and eutrophication. d) consume excess N and P in inland waters and so are essential tools for watershed restoration and management e) occur when aquatic ecosystems are disrupted by invasive species, and can cause pathogenic infections of native species, further enhancing the invasive nature of introduced exotic invaders.

Biology & Microbiology

The genes associated with color blindness and hemophilia are located on the X chromosome. If the recombination frequency between these genes is 25%, what is the genetic map distance between them? Explain how you arrived at your answer, and why calculating recombination frequencies are an important step in creating genetic maps

What will be an ideal response?

Biology & Microbiology

The synthesis of an RNA molecule from a DNA

template strand is a. replication. b. translation. c. transcription. d. DNA synthesis. e. metabolism.

Biology & Microbiology

Which organelles besides the nucleus contain their own DNA?

What will be an ideal response?

Biology & Microbiology