Answer:
- Dependent variable: number of cells that are in one of the phases of mitosis
Explanation:
In an experiment, the independent variable is the variable that is not changed by the other variables that are being measured during the experiment (in this case, the independent variable is represented by the distances from the root cap). On the other hand, the dependent variable is the variable that is being measured/tested during the experimental procedure and, therefore, is 'dependent' on the independent variable. In consequence, in an experiment, the dependent variable is expected to change as a result of the manipulation of the independent variable.
- Xylem contains tracheids, vessels, xylem parenchyma and xylem fibre.
- Tracheids: They are elongated, tubular dead cells with tapering end walls.
- Vessels: These are also known as trachea. They are elongated, tubular dead cells. They are joined to each other by end to end forming a continuous pipe. The cells are thick and lignified.
- Xylem parenchyma: They are also called wood parenchyma. This is the only living tissue of xylem.
- Xylem fibre: They are dead cells with thick walled fibre.
- Phloem consists of sieve tubes, companion cells, phloem parenchyma and phloem fibres.
- Sieve tubes: These are elongated, tubular living cells arranged in a row, with their perforated end walls forming a sieve. They are non-nucleated. Their protoplasm are inter-connected through sieve plates. They possess vacuoles.
- Companion cell: They are elongated, lens-shaped cells containing dense cytoplasm and prominent nuclei. These cells maintain connection with sieve cells through pits.
- Phloem parenchyma: They are living thin walled parenchyma cells.
- Phloem fibre: They are also known as bast fibre. They are elongated fibre like sclerenchymatous dead cells with thick walls containing pits and interlocked ends. Phloem fibre are the only dead cells in phloem.
Hope you could get an idea from here.
Doubt clarification - use comment section.
<span>Compared with developing countries, developed countries have high birth rates. - This statement is not true.
</span><span> With the help of family planning and education, birth rates can be decreased. - This statement is true.
</span><span>If the trend of rising birth rates continues, the population will increase and natural resources will likely start becoming scarce. - This statement is true.
</span><span>When food resources disappear, it eventually leads to food security in certain regions of the world. - This statement is false.</span>
The answer is C plants do photosynthesis to make their own food however animals do not
Answer:
c. Factors 1 and 2 may be influenced by both nature and human factors
Explanation:
The sea level rising and the change in the atmospheric gases are both processes that are influenced by the nature, as well as by the human activities. Naturally, the earth has its own cycles, known as Milankovich cycles, through which the Earth warms up, or cools down, resulting in change of the atmospheric gases, and in accordance to that, change in the sea levels depending on the global climate. The humans to have become a big factor in the past few hundred years. The reason for that is that the humans with their activity started to release lot of greenhouse gases into the atmosphere, especially CO2 and methane. That has been changing the composition of the atmosphere, and the temperatures have been rising. The higher the temperatures, the more ice is melting around the poles and on the high mountains, resulting in an increase in the sea levels.
