When you step on a sharp rock, your<span> leg</span> goes<span> upward and just a moment later you feel pain in your foot. The fact that your leg goes upward is caused by automatic reflex actions by neuron combinations called reflex arcs. Stepping on a sharp rock for example, a sensory neuron </span><span>transports an impulse to an </span><span>interneuron in the spinal cord. The interneuron come together with motor neurons that pull your foot away from the sharp </span>object. The<span> interneuron also come together with motor neurons that control the muscle </span>leg. The muscle legs adjust your position so you don not fall over. The interneuron come together with the other neurons so that you become conscious about what just happened and can take some actions.<span> </span>
Answer:
False
Explanation:
The histones that are more positively charged, tight hardly to negatively charged DNA. So, enzymes, such as acetyltransferases, that reduce the positive charge of histones promote transcription.
Chromatin structure and its modifications can change the package of the DNA and consequently, alter the gene expression. The most common modifications of the chromatin are covalent modifications such as acetylation/deacetylation (by acetyltransferases and eacetylases), methylation (by methyltransferases), and phosphorylation (by kinases). This is the way of gene expression regulation.
The effects of modifications are different, for example methylation promotes condensation of the chromatin and as a consequence, prevents binding of transcription factors to the DNA (transcription is repressed).
Acetylation loosens the association between nucleosomes and DNA (because it neutralizes the positive charge of histones) and consequently promotes transcription. Deacetylation is a process opposite to acetylation.
Answer:
Hope this is helpful! Sorry if my answer is choppy.
Explanation:
Biotic and abiotic features are both important in ecosystems because for example, a biotic factor like a plant, relies on an abiotic factors like the rain and the sun. If the rain were non existent, then the plants would no longer be alive causing a chain reaction in the food system. Biotic factors like plants and animals that are non existent can also cause negative effects in biomes and ecosystems.
Answer:
This question is incomplete
Explanation:
Experimentally, when trying to determine the concentration of an unknown sample of CuSO₄ with known absorbance, a standard curve is used. The standard curve is a scattered plot/graph in which known concentrations and there respective/corresponding absorbance are plotted on a "X and Y axis" graph (scattered plot). The absorbance is represented on the y-axis while the concentration is represented on the x-axis.
Once this known values are plotted on the standard curve, an unknown value (either absorbance or concentration) can be extrapolated from the curve. What is missing from the question is data required for the standard curve.
This question shows the absorbance of the CuSO₄ has been determined (most likely using spectrophotometer), the concentration could have been extrapolated from a standard curve.
An example of a standard curve is provided in the attachment for guidance.
