Answer:
DNA restriction enzymes cut the DNA molecule, while DNA ligases join the resulting DNA fragments
Explanation:
Transformation is a naturally occurring process by which bacteria incorporate exogenous genetic material from their surrounding environment. This process (transformation) is used for DNA cloning via plasmid vectors. In DNA cloning, transformation occurs after restriction enzymes cut the DNA at specific sequences named palindromic sequences (i.e, sequences that can be read the same in opposite direction). Restriction enzymes can generate sticky-ends, where enzymes make staggered cuts in the two strands (e.g., <em>BamH</em>), or blunt ends, where the resulting strands are of the same length (e.g., <em>HaeIII</em>). In general, sticky-end enzymes are more useful because they generate a 3' overhang in one molecule and a complementary 5' overhang in the other, increasing the yield and specificity of ligation. During ligation, a DNA ligase is used to join both DNA strands by forming phosphodiester bonds in the plasmid. Following transformation, bacteria can be selected on antibiotic plates.
The correct answer is: A) pontine respiratory centers
The respiratory centre in the pons is responsible for generating and maintaining the rhythm of respiration. Besides this elementary function, it also has the ability to adjust respiration rhythm in c response to physiological changes. Respiratory centre consists of three major respiratory groups of neurons:
• The dorsal respiratory group (DRG)- initiates inspiration (inhalation)
• the ventral respiratory group (VRG)-responsible for exhalation
• Pontine respiratory group- includes the pneumotaxic (controls both the rate and the pattern of breathing) and apneustic centers (promotes inhalation by sending signals to dorsal group).
Answer:
If photosynthesis stopped, most living organisms on Planet Earth, including humans, would die due either (A) to a shortage of energy because no food molecules would be available or (B) to a shortage of oxygen for cellular respiration.
<span>Both the mushroom and the gecko are heterotrophs: they need to acquire their food from other sources. The tree, on the other hand, is an autotroph--it gains most of its nutritional needs through photosynthesis.</span>
