The atomic number of an isotope is the number of protons it contains, whereas the mass number is the total mass of the nucleus, which is the combined number of protons and neutrons in the nucleus. To find the number of neutrons, you must therefore subtract the atomic number of the isotope from the mass number of the isotope.
<span>In the above example, the atomic number is 8 and the mass number is 18. This isotope is known as O18. The number of neutrons in the isotope is: Mass number - Atomic number = Number of neutrons
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Answer:
Channel proteins form hydrophilic channels to passively transport substances down the concentration gradient.
Carrier proteins bind to substances to transport them actively against the concentration gradient. They do not form channels.
Explanation:
Channel proteins are the membrane proteins that serve in transport of small polar molecules and/or ions by making a hydrophilic pore across the membrane. These molecules diffusion through the pore and exhibit facilitated diffusion.
Carrier proteins are the membrane proteins that transport the substances across the membrane by binding to them. They do not form the hydrophilic channels. Carrier proteins serve in the active transport of molecules against the concentration gradient.
Answer:
Nitrogen is an important nutrient for all plant cells, and it is component of the chlorophyll found in leaves. Which of the following statements best describes how nitrogen is absorbed and distributed to the leaves of the plant so that photosynthesis can take place?
Nitrogen is absorbed by the roots and distributed upwards through the xylem
Explanation:
Nitrogen are gotten from the ground by the plants before it is transported through xylem to the stem and then the leaves
Answer:
plant organisms can alternate between diploid sporophyte and haploid gametophyte phases.
Explanation:
Once mature, the gametophyte produces male and female gametes. When haploid gametes unite, they form a diploid zygote. The zygote grows via mitosis to form a new diploid sporophyte,Thus unlike in animals.
<u>The offspring are genetically unique. </u>
Answer: Option C
<u>Explanation:</u>
Meiosis is a form of cell division that is concentrated towards the reproductive cells. In this cell division the diploid cells (two sets of chromosomes) undergo reduction to form a haploid cell (one set of chromosome). The haploid cell produces sperms and eggs.
Meiosis occurs in two levels Meiosis I and II. Chromosomal segregation happens during meiosis I and II to produce a genetic diversity. The important net result obtained by the meiosis is to produce a genetically unique offspring.
