Answer:
true
Explanation:
<em><u>Some water pollution is caused from “point sources” that is discrete locations, from which pollutants are discharged, e.g., a pipe, ditch, ship, or factory smokestack. Point sources originate in large and easy to trace facilities, hence are easier to control. In contrast, pollution from “nonpoint” sources is cumulative, arising from multiple inputs over larger areas, such as farms, city streets, and residential neighbourhoods. Hence, such sources are harder to precisely identify, and because of this uncertainty, nonpoint source pollution is harder to control than the point source.</u></em>
The process of silk production is known as sericulture. ... Extracting raw silk starts by cultivating the silkworms on mulberry leaves. Once the worms start pupating in their cocoons, these are dissolved in boiling water in order for individual long fibres to be extracted and fed into the spinning reel.
Complete question: <em>"RNA plays important roles in many cellular processes, particularly those associated with protein synthesis: transcription, RNA processing, and translation. Drag the labels to the appropriate bins to identify the step in protein synthesis where each type of RNA first plays a role. If an RNA does not play a role in protein synthesis, drag it to the "not used in protein synthesis" bin.</em>
<em>1. transcription/RNA processing
</em>
<em>2. translation
</em>
<em>3. not used in protein synthesis
</em>
<em>a) snRNA
</em>
<em>b) tRNA
</em>
<em>c) mRNA
</em>
<em>d) RNA primers
</em>
<em>e) pre-mRNA
</em>
<em>f) rRNA</em>
Answer
1. transcription/RNA processing:
<em>a) snRNA</em>
<em>c) mRNA</em>
<em>e) pre-mRNA</em>
2. translation
<em>b) tRNA</em>
<em>f) rRNA</em>
3. not used in protein synthesis
<em>d) RNA primers</em>
Explanation:
There are many RNAs, each in charge of performing a different function.
- preRNA is the precursor of the mature mRNA. These molecules possess long intermediate sequences called introns that do not codify for proteins. It occurs a posttranscriptional modification that eliminates introns and makes the RNA to get mature as mRNA.
- snRNA means <em>"small nuclear RNA"</em>. These are small RNA molecules located in the nucleus and are implicated in the mRNA maturation process. They associate with proteins composing the small nuclear ribonucleoproteins, and their function is to contribute to the initial mARN processing that transcribes from DNA and that must maturate to be exported from the nucleus. These molecules eliminate the introns.
- mRNA means "<em>messenger RNA</em>". These molecules are carriers of the genetic information and are in charge of transporting it from the genome to the ribosomes. They are the mold for the new protein synthesis. Their nucleotide sequence is complementary with the nucleotide sequence of a particular DNA segment.
- rRNA means "<em>ribosomal RNA</em>". They are the principal ribosomal component. Ribosomes are constituted by two subunits. One of them is a big RNA molecule associated with about 20 proteins. The other subunit is composed of three RNA molecules associated with about 50 proteins.
- tRNA means "<em>transference RNA</em>". These molecules are in charge of transferring activated amino acids from the cytosol to the ribosomes where the new protein is being synthesized.
Protein synthesis is initiated when mRNA meets a free ribosome, the primary structure for protein synthesis. Ribosomes can be found in the rough endoplasmic reticulum or floating in the cytosol. They read the mRNA code and add the correct amino acid using transference RNA to build the protein.
Answer:
Receptor tyrosine kinases undergo autophosphorylation.
Explanation:
The receptor tyrosine kinases (RTKs) are proteins that undergo dimerization and autophosphorylation after binding with their corresponding ligands, thereby triggering downstream molecular signaling cascades. The RTKs bind with high specificity to ligands including growth factors, hormones and cytokines. In human cells, there are 58 types of RTKs proteins that function to regulate developmental pathways, and their dysfunctions have been associated with cancer progression.
Answer:
Carbohydrates are molecules composed of carbon, hydrogen, and oxygen, and they include sugars and starches. Carbohydrates can be broken down to provide a source of usable chemical energy for cells.
Explanation: