Answer:
A) The catalyst makes lower energy pathways available.
Explanation:
A catalyst is a substance which speeds up a chemical reaction without itself being used in the reaction. Activation energy is the thresh hold energy which is required to initiate a chemical reaction. In the absence of catalyst, the activation energy is high therefore reactions are slower. But, presence of catalyst lowers the activation energy required to initiate the reaction as a result of which the reaction gets an alternate energy pathway to proceed which is responsible for speeding up the reaction.
Answer:
The importance of the AUG and UGA bases lies in the fact that the first one is a start codon and the second one is a stop codon, respectively (option a).
Explanation:
Codons or triplets are sequences of three nitrogenous bases, in the mRNA, that determine the synthesis of a specific amino acid.
- <em>AUG </em><em>is called the </em><em>initiation or start codon</em><em>, and is usually at the beginning of a peptide synthesis, in addition to encoding the amino acid methionine.
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- <em>UGA</em><em> is a</em><em> termination or stop codon</em><em> found at the end of a petid chain when it is complete. UAA and UAG codons are also STOP or termination codons and, together with UGA, do not code for amino acids.</em>
The biological importance of start and stop codons is to initiate the synthesis of a protein and to stop the addition of amino acids when their size is adequate.
1.
C. Genus and species
Binominal nomenclature: a formal system of naming species of living things, such as humans which are <em>homo sapiens.</em>
2.
A. carbohydrates
any of a large group of organic compounds occurring in foods and living tissues and including sugars, starch, and cellulose.
3.
C. work with other cells
one unicellular organism would quickly die if was not within a colony of very similar unicellular organisms.
4.
C. Bacteria
bacteria are able to cause contagious diseases seeing as a virus, (which can be a contagious disease) is a form of bacteria.
Answer:
chloroplasts and mitochondria.
Explanation:
Chloroplasts and mitochondria are the organelles capable of ATP production by photophosphorylation and oxidative phosphorylation respectively. Chloroplasts are the site for photosynthesis. The light reactions of photosynthesis include splitting of the water molecule in presence of sunlight and transfer of electrons from PS-II to PS-I via electron carrier. During electron transport, a proton gradient is created which in turn drives ATP synthesis.
Mitochondria are the site for aerobic stages of cellular respiration. Glycolysis and Kreb's cycle, the first and second stages of cellular respiration produce NADH and FADH2 during the redox reactions. These reducing powers are oxidized by giving their electrons to the terminal electron acceptor, the oxygen molecule.
Electrons from the reducing powers are carried to oxygen molecules via a series of electron carrier proteins embedded in the inner mitochondrial membrane. During electron transport, an electrochemical gradient is created which in turn drives the ATP synthesis.