Sabemos que la vida comenzó hace al menos 3.500 millones de años, porque esa es la edad de las rocas más antiguas con evidencia fósil de vida en la tierra. Estas rocas son raras porque los procesos geológicos posteriores han remodelado la superficie de nuestro planeta, a menudo destruyendo rocas más viejas y creando otras nuevas (lo siento si es un amor incorrecto, marque como más inteligente si es correcto).
Fresh water is any body of water with a low salt concentration. Organisms in fresh water various challenges which includes; Osmotic concentration such that fresh water is permanently dilute and most cells cannot function at this concentration of ions. Varying temperatures, variation in oxygen levels and reproduction and life cycle due to permanence of habitat and physiological difficulty of regulating osmotic concentration in larvae and juveniles.
Answer:
a Anaphase I
b Metaphase I
c Telophase I
d Anaphase II
e Prophase I
f Telophase II
Explanation:
Prophase I begins after the DNA has been duplicated, as shown in picture e. The chromosomes are condensed, and also visible, which is apparent in picture e.
The next stage is called Metaphase I, in which the pairs of homologous chromosomes align at The the centre of the cell and the spindle fibres attach, as shown in picture b.
The pairs of chromosomes are pulled apart to opposite poles of the cell by the spindle fibres., as shown in picture a. This stage is called Anaphase I.
Then, a process called Telophase I occurs, when the cell divides into two daughter cells. One of these cells is shown in picture c.
Picture d shows the stage Anaphase II, where the spindle has attached and the chromatids are pulled to the opposite poles of the cell.
The final picture left is picture f, which shows the daughter cell at the end of meiosis II, where the nuclear envelope is reforming, as in telophase II.
