Answer:
The correct answer is option B, that is, promoter, operator, gene.
Explanation:
In a prokaryote, just in front of the operator, the promoter is located, and just in front of the structural genes, the operator is located. All these in combination give rise to an operon.
Any gene, which codes for an enzyme or a structural protein is termed as a structural gene, in the lac operon, a structural gene codes for three distinct kinds of enzymes. A short sequence of DNA is situated just in front of the structural gene, which is known as the operator. An operator functions as a switch for transcription, that is, it monitors whether the process of transcription will take place or not.
Just in front of an operator, a sequence of a promoter is present, and for the transcription and translation of all the structural genes, the RNA polymerase needs to combine first with the promoter. In case, if no transcription is to take place, then the operator allows the repressor to bind with it and prevent the attachment of RNA polymerase with the promoter. Hence, the correct sequence of a prokaryotic operon is a promoter, operator, and gene.
Answer:
The correct answer will be- Meiosis I, anaphase I
Explanation:
Alleles are the variant alternative forms of a gene which determines the trait of an organism. The trait or phenotype is expressed only when the two alleles controlling a single trait on separate chromosomes are aligned in a complementary position.
During gamete formation, the alleles controlling a trait segregate independently of each other. This segregation of alleles takes place during Anaphase I of meiosis I. During anaphase, the sister chromatids are separated by the mitotic spindles so that the chromosomes can reach the opposite poles.
Thus, Meiosis I, anaphase I am the correct answer.
ATP consists of three phosphates, a base (adenine) and a sugar (ribose).
Answer:
Unlike the queen bee, which has 32 chromosomes, drones have half the chromosomal charge (n= 16), so they are considered haploid.
Explanation:
The system of determination of the sex in the bees —like in other insects— is called haplodiploidy, and consists of which the females of the species possess complete charge of chromosomes, whereas the males only possess half. This is what happens with the queen bee with 32 chromosomes, while drones only have 16 chromosomes, so they are considered haploid.
Additionally, as a characteristic of haplodiploidy, males only proceed from female gametes, so they can only contribute gametes to produce females of the species.
The other options are not correct because:
- <em>Drones, with half of the chromosomal charge, </em><u><em>cannot be diploid</em></u><em>.
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- <u><em>Monosomy and trisomy</em></u><em> are defects in the distribution of chromosomes during meiosis, which imply one chromosome less or one chromosome more in the normal chromosome charge respectively.</em>
Ionic bonding?
the bonding between non-metals and metals
non-metals form negative ions, so they are attracted to metals, which form postive ions