List the characteristics of a mechanical wave. your answer

Which type of RNA interacts with nuclear proteins to form a ribonucleoprotein complex responsible for intron removal? a) snRNA b

Gennadij [26K]

Answer:

a) snRNA

Explanation:

The association of small nuclear RNA (snRNA) and some specific proteins forms small nuclear ribonucleoprotein complexes. Some complexes are spliceosomes, molecular machines -made up of a snRNA and about 80 proteins- that remove introns from pre-mRNAs via successive phosphoryl transfer reactions.

4 0

3 years ago

1.Which of these statements is classified as inference?

irina1246 [14]

What are the statements?

an inference is a conclusion reached on the basis of evidence and reasoning
examples:
if you see someone eating a new food and he or she makes a face, then you infer he does not like it
if someone slams a door, you can infer that she is upset about something.

4 0

3 years ago

What are the stages of mitosis in detail

disa [49]

Mitosis begins with prophase, during which chromosomes recruit condensin and begin to undergo a condensation process that will continue until metaphase. In most species, cohesin is largely removed from the arms of the sister chromatids during prophase, allowing the individual sister chromatids to be resolved.

Prometaphase begins with the abrupt fragmentation of the nuclear envelope into many small vesicles that will eventually be divided between the future daughter cells. The breakdown of the nuclear membrane is an essential step for spindle assembly.

Next, chromosomes assume their most compacted state during metaphase, when the centromeres of all the cell's chromosomes line up at the equator of the spindle. Metaphase is particularly useful in cytogenetics, because chromosomes can be most easily visualized at this stage. Furthermore, cells can be experimentally arrested at metaphase with mitotic poisons such as colchicine.

The progression of cells from metaphase into anaphase is marked by the abrupt separation of sister chromatids. A major reason for chromatid separation is the precipitous degradation of the cohesin molecules joining the sister chromatids by the protease separase.

Mitosis ends with telophase, or the stage at which the chromosomes reach the poles. The nuclear membrane then reforms, and the chromosomes begin to decondense into their interphase conformations. Telophase is followed by cytokinesis, or the division of the cytoplasm into two daughter cells. The daughter cells that result from this process have identical genetic compositions.

5 0

3 years ago

In tomato plants, the allele for purple stems is dominant to allele for green stems and the allele for red fruit is dominant to

Kamila [148]

So let's call the allele that is dominant for purple stems is P, and the recessive allele yielding green stems is p. And let's say that the allele that is dominant for red fruit is R and the recessive allele for yellow fruit is r.

The two plants are each heterozygour for both traits, meaning that the cross is going to be:

PpRr x PpRr

So let's setup a Punnet Square:

$\left[\begin{array}{ccccc}&PR&Pr&pR&pr&PR&PPRR&PPRr&PpRR\4&PpRr&Pr&PPRr&PPrr&PpRr&Pprr\\pR&PpRR&PpRr&ppRR&ppRr&pr&PpRr&Pprr&ppRr&pprr\end{array}\right]$

The genotypic ratios (alleles) and phenotypic ratios are as follows:

PPRR (Purple stem, Red fruit): $\frac{1}{16}$

PpRR (Purple stem, Red fruit): $\frac{2}{16}$ or $\frac{1}{8}$

ppRR (Green Stem, Red fruit): $\frac{1}{16}$

PPRr (Purple stem, Red fruit): $\frac{2}{16}$ or $\frac{1}{8}$

PPrr (Purple stem, Yellow fruit): $\frac{1}{16}$

PpRr (Purple stem, Red fruit): $\frac{4}{16}$ or $\frac{1}{4}$

pprr (Green stem, Yellow fruit): $\frac{1}{16}$

ppRr (Green stem, Red fruit): $\frac{2}{16}$ or $\frac{1}{8}$

Pprr (Purple stem, Yellow fruit): $\frac{2}{16}$ or $\frac{1}{8}$

So then we take the like phenotypic ratios and add them together:

Purple stem, Red fruit: $\frac{1}{16} +\frac{2}{16} +\frac{2}{16} +\frac{4}{16}=\frac{9}{16}$

Green stem, Red fruit: $\frac{1}{16}+ \frac{2}{16} =\frac{3}{16}$

Purple stem, Yellow fruit: $\frac{1}{16}+ \frac{2}{16} =\frac{3}{16}$

Green stem, Yellow fruit: $\frac{1}{16}$

6 0

3 years ago

What is the effect of the cap protein on the transcription level of the lac operon?

Gnesinka [82]

Answer:

The lac repressor senses lactose indirectly, through its isomer allolactose. Catabolite activator protein (CAP) acts as a glucose sensor. It activates transcription of the operon, but only when glucose levels are low. CAP senses glucose indirectly, through the "hunger signal" molecule cAMP.

4 0

3 years ago