Answer:
There are 64 fish, 8 ducks and 4 turtles.
Explanation:
From the question, there can be from 2 to 99 fish in the pond. However, there cannot be fractions in the number of fish, ducks or turtles. Hence, the number of fish must have both of a perfect square and perfect cube. The perfect squares from 2 to 99 are 4, 9, 16, 25, 36, 49, 64 and 81. The perfect cubes from 2 to 99 are 8, 27 and 64. Since only 64 fits both criteria, the number of fish is 64. The number of ducks is the square root of number of fish, which is the square root of 64. The square root of 64 can be either positive 8 or negative 8. However, there cannot be negative numbers, so there are 8 ducks in total. The number of turtles is the cube root of the number of fish, which is the cube root of 64 and it is 4.
Answer:
Explanation:
We can easily move the box from a ground floor though to the first floor at an angle of 40° to the horizontal by simply pushing the load through an inclined plane. We will simply be lean the inclined plane on the building at the required angle and the push through the the height of the building.
Based on the explanation above, the best type of simple machine to use is an INCLINED PLANE. <em>Note that the essence of using a machine is simply to make our work easier and faster and also be able to overcome a much larger load with a minimal effort. </em>
1.1
Meiosis I
The first meiotic division: diploid → haploid
Prophase I: Chromosomes condense, nuclear membrane dissolves, homologous chromosomes join and occurs crossing over.
Metaphase-I: the homologous chromosomes align in the middle of the cell. Spindle fibers from the centrosomes connect to the chromosomes.
Anaphase -I: Spindle fibers contract and split the homologous chromosomes, moving them to opposite poles of the cell.
Telophase -I: Chromosomes decondense; cell divides to form two haploid cells.
1.2 Meiosis II
The second division: separates sister chromatids (these chromatids may not be identical due to crossing over in prophase I)
Prophase II: Chromosomes condense, nuclear membrane dissolves, centrosomes move to opposite poles (perpendicular to before)
Metaphase-II: the chromosomes align in the middle of the cell. Spindle fibers from the centrosomes connect to the chromosomes (at the centromere)
Anaphase-II: Spindle fibers contract and split the sister chromatids, and moves them to opposite poles of the cell.
Telophase-II: Chromosomes decondense,cells divides again to form another 2 haploid daughter cells. Final: 4 new cells.
2. The differences:
Mitosis:
- has 1 division per cycle
- one cell produces 2 new cells
- the genetic information in the mother-cell and the daughter-cells are the same. ( the number of chromosomes is also the same)
- it occurs in somatic cells
Meiosis:
- two divisions per cycle
- one cell when divides produces 4 new cells
- the new cells have different genetic information. mixes the genetic material from the parent cells
- the number of chromosomes of the daughter cells is half of the mother's.
3. Prokaryotic organisms don't divide through mitosis, they use a different process called binary fission. Only eukaryotic organisms, or those whose cells have a defined nuclei, undergo mitosis. Bacteria, for example, are prokaryotic organisms that use binary fission.
4.
It can't occur. Cross over is the exchange of DNA between homologous chromosomes. That will result in recombinant chromosomes during sexual reproduction. It can't occur on different chromosomes because they don't code for the same genes.
5. There are a lot of different theories about that, but it's mostly believed that meiosis must evolve before sexual reproduction. That's because The cell replicates their information first and then divides. Plus the cell does that even though it didn't recombine DNA with another organism (sexual reproduction).
Answer:
I think you're referring to the Metaphase...
Explanation:
During Cell Division (or, rather before!) the DNA needs to be replicated. This normally is done by DNA Polymerase, and results in two identical double strands (the "Sister Chromatids".
These chromatids are held together at the Centromere, which will be the heart of the "X"-shape. After that the DNA is packed into Chromosomes by winding it around proteins called Histones. If I remember correctly there are 5 different Histones.
This "Zipping Up" makes the chromosomes more visible.
As the two sister chromatids are still connected, the result is the X-shaped Metaphase Chromosome....
Answer:
i would pick the answer c
Explanation:
sexual reproduction is slower than asexual reproduction because in order to reproduce sexually, you would need to find a partner first. but reproducing asexually is quicker because you don't need a partner