Answer:
They consist mainly of iron-nickel metal with small amounts of sulphide and carbide minerals. During the decay of radioactive elements in the early history of the solar system, many asteroids melted and the iron they contained, being dense, sank to the centre to form a metallic core.
Explanation:
Hope this helps luv
They both Break down characteristics of organisms, this is a general statement, it can apply to anything as well
Answer:
A). True
Explanation:
tRNA, which means transfer RNA is one of the three types of RNA known in nature. The tRNA is found in the ribosome, where it plays a pivotal role in protein synthesis (translation). Transfer RNA is the RNA responsible for reading the nucleotides in the mRNA codon and carrying the amino acid that corresponds those codons to the ribosome.
The tRNA has a 3-dimensional structure that allows it to carry anticodon that reads codon and also carry amino acids on opposite ends. Hence, according to this question, tRNA is a type of RNA that delivers amino acids to the ribosome during protein synthesis.
Answer:
Please find the detailed explanation of this statement below
Explanation:
Firstly, a repressed gene is a gene whose expression has been inhibited or repressed. The lac operon in E.coli bacteria is a regulatory unit containing structural genes, a single promoter and operator regions. The promoter is the region where the transcription enzyme (RNA polymerase) binds to in order to transcribe the genes in the lac operon. The structural genes in the lac operon can only be expressed in the presence of lactose sugar.
However, in the absence of lactose, LAC REPRESSOR, which is a transcription factor (protein), prevents the binding of RNA polymerase to the PROMOTER region by binding to the OPERATOR region of the lac operon. This inhibits the expression of the lactose genes in the operon.
Note that, the structural genes in the lac operon (lacZ, lacY, lacA) code for proteins that help break down lactose sugar for energy in the E.coli bacteria. Therefore, a bacteria cell with a repressed lac operon will be unable to degrade lactose sugar.
