Answer: b. one atom transfers an electron to another atom
Explanation:
An ionic bond is also called as the electrovalent bond. It is a type of linkage that is formed by the electrostatic attraction formed between ions of opposite charge in a chemical compound.
These bonds are formed when the valence electrons from one of the atom are transferred to the another atom.
Answer: C
Explanation: The process that occurred in the lake is natural selection. In the presence of an external environmental influence such as pollution, only the trouts that were fit to survive or in other words those that have the alleles that help in adapting to the new conditions live and increased in numbers. In such a case, one can say the fittest of the organisms survived and the corresponding allelic frequency in that population increased over time. The organisms carrying the other alleles died due to pollution and hence the overall frequency of alleles change.
Answer:
The process of respiration in plants involves using the sugars produced during photosynthesis plus oxygen to produce energy for plant growth. In many ways, respiration is the opposite of photosynthesis. In the natural environment, plants produce their own food to survive.As with photosynthesis, plants get oxygen from the air through the stomata. Respiration takes place in the mitochondria of the cell in the presence of oxygen, which is called "aerobic respiration".
In plants, there are two types of respiration: dark respiration and photo respiration. The first kind occurs in the presence or absence of light, while the second occurs exclusively in the presence of light.<em>Plant respiration occurs 24 hours per day</em>, but <em>night respiration is more evident since the photosynthesis process ceases.</em> During the night, it is very important that the <em>temperature is cooler than during the day</em> because plants can experience stress. Imagine a runner in a marathon.
roots respire too!
One of the functions of the substrate is <em>to serve as a site for air exchange between the root zone and atmosphere</em>. In other words, <em>roots breathe oxygen like we do</em>. Different plants have different oxygen requirements for their root systems.
For example,
<em><u>the root system of a poinsettia requires a lot of oxygen, so it is best to use a substrate with high air porosity, while hostas can live well in a substrate with a high water holding capacity. </u></em>
The cell membrane folds upon itself easily, which facilitates cellular reproduction by mitosis.
<span>The membrane is a flexible, fluid mosaic and changes shape easily to create holes for substances to move in and out of the cell. </span>
<span>The outer layer of the membrane is hydrophilic, which allows water to flow in and out of the cell easily to eliminate waste. </span>
<span>The proteins that are embedded in the cell membrane act as channels to transport substances in and out of the cell.</span>
