Answer:
a) The resources which can be regenerated and replaced at the shorten period of time is called renewable source of energy.
b) The different forms of energy are:
1) Mechanical energy
2) Heat energy
3) Light energy
4) Chemical energy
5) Sound energy
6) Electrical energy
c) The resources which cannot be replaced shortly after they are finished is called non-renewable sources of energy. For example: coal, petrol, minerals etc.
e) The energy which affects the magnetic bodies is called magnetic energy .
Answer: 2, 4 and 5.
Explanation:
Human system are made of various organs which in turn are made up of various tissues which in turn are made up of various cells. Cells are therefore much more numerous than systems.
As already mentioned, organs are made up of tissues which are made up of cells so statement 4 is right.
As systems are made up of various organs working together, they are more complex than the individual organs. For instance, the Muscular system is more complex than the triceps or bicep muscles.
Answer: RNAs are not processed before translation in prokaryotes, this process only takes place in eukaryotes.
Explanation:
Messenger RNA or mRNA is a single-straded ribonucleic acid that transfers the genetic information from the DNA (deoxyribonucleic acid) molecule of the cell nucleus to a ribosome (which are the machinery responsible for protein synthesis) in the cytoplasm. mRNA determines the order in which the amino acids of a protein will be joined and acts as a template or pattern for the synthesis of that protein. To accomplish this, the DNA molecule must be transcribed into an RNA molecule, which is used for protein synthesis.
The messenger RNA obtained after transcription is known as primary transcribed RNA or precursor RNA or pre-mRNA, which in most cases is not released from the transcription complex in a fully active form, but in eukaryotes it must undergo modifications before it can perform its function (RNA processing or maturation). These modifications include:
- Elimination of fragments (splicing): In most cases, the <u>mRNA undergoes the removal of internal, non-coding sequences called introns, and the connection of exons. This does not occur in prokaryotic cells</u>, as they do not have introns in their DNA.
- Protection by CAP: <u>Addition to the 5' end of the structure called "cap" or "capping"</u>, which is a modified guanine nucleotide, 7-methylguanosine triphosphate, via a 5'-5' triphosphate linkage, instead of the usual 3',5'-phosphodiester linkage. This cap is necessary for the normal RNA translation process and to maintain its stability.
- Polyadenylation signal: <u>Addition to the 3' end of a poly-A tail, a long polyadenylate sequence, whose bases are all adenine</u>. Its addition is mediated by a sequence or polyadenylation signal (AAAAAA), located 11-30 nucleotides upstream of the original 3' end. This tail protects the mRNA from degradation, and increases its half-life in the cytosol, so that more protein can be synthesized.
The mature mRNA (in eukaryotes) is transferred to the cytosol of the cell through pores in the nuclear envelope. Once in the cytoplasm, ribosomes are coupled to the mRNA. However, in prokaryotes, ribosome binding occurs while the mRNA strand is being synthesized. After a certain amount of time, the mRNA is degraded into its component nucleotides by ribonucleases. So, the transcription and translation processes are carried out in a similar way as in eukaryotic cells but they occur simultaneously. But, the fundamental difference is that, in prokaryotes, the messenger RNA does not undergo a maturation process and, therefore, no cap or tail is added and no introns are removed. Moreover, it does not have to leave the nucleus as in eukaryotes, because in prokaryotic cells there is no defined nucleus.
So, RNAs are not processed before translation in prokaryotes, this process only takes place in eukaryotes.
Meter
Inch
I think it those
Answer:
mass₁=100.0g
time₁=2.70 days
mass₂=x
time₂=8.10 days
8.10/2.70 = 3
100/2 = 50/2 = 25/2 = 12.5 g
x=12.5 g
