Answer:
Cells divide to reproduce. There are two primary methods used, one for somatic cells, which compose the organism’s body, and one for reproductive cells, or gametes.
Scientists call the process of somatic cell division mitosis. Mitosis has six distinct steps in which the cell organizes and copies the DNA in the nucleus. Once copied, each new cell has its own copy of the DNA. The six steps of mitosis are prophase, prometaphase, metaphase, anaphase, telophase and cytokinesis. Some authorities consider the non-dividing portion of the cell’s lifecycle, known as interphase, to be one of seven steps involved in mitosis; however, interphase cells are not actively dividing.
Sex cells, such as sperm or eggs, must divide differently. Sex cells only possess one-half of the DNA that makes up a new animal. That way, when they combine, the resulting organism gets half of its DNA from its mother and half from its father. Because sex cells only want half of the DNA in each cell, they go through a different division process called meiosis. In meiosis, the cells split a second time, which yields four daughter cells rather than two as with mitosis; however, this provides each daughter cell with 23 chromosomes in contrast to the 46 chromosomes in somatic cells.
Answer: Although the best-known cause of a mass extinction is the asteroid impact that killed off the non-avian dinosaurs, in fact, volcanic activity seems to have wreaked much more havoc on Earth's biota. Volcanic activity is implicated in at least four mass extinctions, while an asteroid is a suspect in just one. Examples, of mass extinctions are Permian extinction of marine species, and Cretaceous extinction of various species, including dinosaurs.
Answer:
The final temperature is 348.024°C.
Explanation:
Given data:
Specific heat of copper = 0.385 j/g.°C
Energy absorbed = 7.67 Kj (7.67×1000 = 7670 j)
Mass of copper = 62.0 g
Initial temperature T1 = 26.7°C
Final temperature T2 = ?
Solution:
Specific heat capacity:
It is the amount of heat required to raise the temperature of one gram of substance by one degree.
Formula:
Q = m.c. ΔT
Q = amount of heat absorbed or released
m = mass of given substance
c = specific heat capacity of substance
ΔT = change in temperature
ΔT = T2 - T1
Q = m.c. ΔT
7670 J = 62.0 g × 0.385 j/g °C ×( T2- 26.7 °C
)
7670 J = 23.87 j.°C ×( T2- 26.7 °C
)
7670 J / 23.87 j/°C = T2- 26.7 °C
T2- 26.7 °C = 321.324°C
T2 = 321.324°C + 26.7 °C
T2 = 348.024°C
The final temperature is 348.024°C.
Answer:
2H+(aq) + 2OH-(aq) → 2H2O(l)
Explanation:
Step 1: The balanced equation
2HCl(aq)+Ca(OH)2(aq) → 2H2O(l)+CaCl2(aq)
This equation is balanced, we do not have the change any coefficients.
Step 2: The netionic equation
The net ionic equation, for which spectator ions are omitted - remember that spectator ions are those ions located on both sides of the equation - will.
2H+(aq) + 2Cl-(aq) + Ca^2+(aq) + 2OH-(aq) → 2H2O(l) + Ca^2+(aq) + 2Cl-(aq)
After canceling those spectator ions in both side, look like this:
2H+(aq) + 2OH-(aq) → 2H2O(l)
