Answer:
Normal Strand: alanine - methionine - histidine
Mutated Strand: glutamine - cysteine - no third amino acid.
Explanation:
<h3>mRNA Structure</h3>
Messenger ribonucleic acid (mRNA) is the RNA that is used in cells for protein synthesis. It has a single strand made by the transcription of DNA by RNA polymerase. It contains four nucleotides: Adenine (A), Guanine (G), Cytosine (C), and Uracil (U).
<h3>DNA Replication</h3>
Before transcribing, we need to create the complementary strand of the DNA. We're going to write out the nucleotides of the complementary strand by matching the nucleotides in these pairs: (A & T) and (C & G).
Normal Strand: GCA ATG CAC
Complementary Strand: CGT TAC GTG
Next, we can transcribe this to find our mRNA. We're going to do the same thing to the complementary DNA strand, but with Uracils instead of Thymines. So our pairs are: (A & U) and (C & G)
Complementary DNA Strand: CGT TAC GTG
mRNA Strand: GCA AUG CAC
You'll notice that the mRNA strand is almost exactly like the new mRNA strand, but with Uracil instead of Thymine.
<h3>Reading Codons</h3>
Each set of three nucleotides is known as a codon, which encodes the amino acids that ribosomes make into proteins. To read the codons, you need to have a chart like the one I attached. Start in the middle and work your way to the edge of the circle. Some amino acids have multiple codons. There are also "stop" and "start" codons that signify the beginning and ends of proteins.
mRNA Strand: GCA AUG CAC
Amino Acids: Ala Met His
Our sequence is alanine, methionine, and histidine.
<h3>Frameshift Mutations</h3>
A frameshift mutation occurs when a nucleotide is either added or removed from the DNA. It causes your reading frame to shift and will mess up every codon past where the mutation was. This is different than a point mutation, where a nucleotide is <em>swapped</em> because that will only mess up the one codon that it happened in. Frameshift mutations are usually more detrimental than point mutations because they cause wider spread damage.
<h3>Mutated Strand</h3>
Let's repeat what we did earlier on the mutated strand to see what changed.
Mutated Strand: CAA TGC AC
Complementary Strand: GTT ACG TG
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Complementary DNA Strand: GTT ACG TG
mRNA Strand: CAA UGC AC
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mRNA Strand: CAA UGC AC
Amino Acids: Glu Cys X
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Our amino acid sequence is glutamine, cysteine, and no third amino acid.
As you can see, removing the first nucleotide of the strand caused every codon to change. The last codon is now incomplete and won't be read at all. If this happened in a cell, the protein that was created from this mutated strand would be incorrect and may not function completely or at all.
The human respiratory system<span> is a series of organs </span>responsible<span> for taking in oxygen and expelling carbon dioxide. The primary organs of the </span>respiratory system<span> are lungs, which carry out this exchange of gases as we breathe.</span>
Answer:The answer is A
Explanation:I have had the question before
Answer:
a) i) Xylem
ii) Upper epidermis
iii) Stoma
iv) Chroloplast
v) Palisade cell layer
b) By a waxy layer on the cuticle of the leaf
Explanation:
The plant's leaves have a large surface area that is capable of absorbing sunlight. The plant's waxy layer in the surface of the leaf protects it from the loss of water, as well as of diseases caused by the entry of microorganisms. The palisade cell's surface is a single layer of cells underneath the upper epidermis that is adapted to absorb light energy.
The waxy layer is a primary physical barrier composed of insoluble polymers and lipids whose function is to protect the leaves against the entry of harmful organisms including virus, bacteria and fungus. Moreover, the plant's waxy cuticle is also a barrier that prevents the loss of water and solutes.
Answer:The Food Chain: The answer has to do with trophic levels. As you probably know, the organisms at the base of the food chain are photosynthetic; plants on land and phytoplankton (algae) in the oceans. These organisms are called the producers, and they get their energy directly from sunlight and inorganic nutrients. The organisms that eat the producers are the primary consumers. They tend to be small in size and there are many of them. The primary consumers are herbivores (vegetarians). The organisms that eat the primary consumers are meat eaters (carnivores) and are called the secondary consumers. The secondary consumers tend to be larger and fewer in number. This continues on, all the way up to the top of the food chain. About 50% of the energy (possibly as much as 90%) in food is lost at each trophic level when an organism is eaten, so it is less efficient to be a higher order consumer than a primary consumer. Therefore, the energy transfer from one trophic level to the next, up the food chain, is like a pyramid; wider at the base and narrower at the top. Because of this inefficiency, there is only enough food for a few top level consumers, but there is lots of food for herbivores lower down on the food chain. There are fewer consumers than producers.
Land and aquatic energy pyramids
Trophic Level Desert Biome Grassland Biome Pond Biome Ocean Biome
Producer (Photosynthetic) Cactus Grass Algae Phytoplankton
Primary Consumer (Herbivore) Butterfly Grasshopper Insect Larva Zooplankton
Secondary Consumer (Carnivore) Lizard Mouse Minnow Fish
Tertiary Consumer (Carnivore) Snake Snake Frog Seal
Quaternary Consumer (Carnivore) Roadrunner Hawk Raccoon Shark
Food Web: At each trophic level, there may be many more species than indicated in the table above. Food webs can be very complex. Food availability may vary seasonally or by time of day. An organism like a mouse might play two roles, eating insects on occasion (making it a secondary consumer), but also dining directly on plants (making it a primary consumer). A food web of who eats who in the southwest American desert biome might look something like this:
Explanation:
