Answer:
Explanation:
some gases prevent the escape of heat from the earth.There will be an increase in the percentage of such gases would cause the average temperatures to increase world wide.This is known as greenhouse effect.Carbon dioxide is one of the green house gases.An increase in the carbon dioxide content in the atmosphere woul cause more heat to be retained by the atmosphere and lead to global warming.
C. The material for it is super expensive and sometimes fragile, which sucks, but it's true.
Answer:
Jacob and Monod were intellectually primed to draw the conclusions they did concerning regulation of the lac operon. In part, this was due to their fascination with mechanisms of enzyme regulation. They knew that the activity of some enzymes is regulated when their reaction product binds to the enzyme, changing its shape and therefore its activity. This knowledge allowed them to easily make the intellectual leap to propose B) allosteric regulation of the repressor
Explanation:
When we talk about the mechanisms of enzyme regulation, we refer to allosteric regulation of the repressor. The Allosteric control of transcriptional regulatory proteins allows organisms to react to changes in environmental and metabolic conditions. Also, it is s a thermodynamic phenomenon. When it binds one molecule, the affinity with which a protein binds to a second molecule is altered.
<span>There are numerous proteins in muscle. The main two are thin actin filaments and thick myosin filaments. Thin filaments form a scaffold that thick filaments crawl up. There are many regulatory proteins such as troponin I, troponin C, and tropomyosin. There are also proteins that stabilize the cells and anchor the filaments to other cellular structures. A prime example of this is dystrophin. This protein is thought to stabilize the cell membrane during contraction and prevent it from breaking. Those who lack completely lack dystrophin have a disorder known as Duchene muscular dystrophy. This disease is characterized by muscle wasting begininng in at a young age and usually results in death by the mid 20s. The sarcomere is the repeating unit of skeletal muscle.
Muscle cells contract by interactions of myosin heads on thick filament with actin monomers on thin filament. The myosin heads bind tightly to actin monomers until ATP binds to the myosin. This causes the release of the myosin head, which subsequently swings foward and associates with an actin monomer further up the thin filament. Hydrolysis and of ATP and the release of ADP and a phosphate allows the mysosin head to pull the thick filament up the thin filament. There are roughly 500 myosin heads on each thick filament and when they repeatedly move up the thin filament, the muscle contracts. There are many regulatory proteins of this contraction. For example, troponin I, troponin C, and tropomyosin form a regulatory switch that blocks myosin heads from binding to actin monomers until a nerve impulse stimulates an influx of calcium. This causes the switch to allow the myosin to bind to the actin and allows the muscle to contract. </span><span>
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