arbon, as with many elements, can arrange its atoms into several different geometries, or "allotropes." In pure diamond, every carbon atom is covalently bonded to exactly 4 other carbon atoms in a very specific and energetically favorable geometry. The diamond cannot be broken or scratched unless many covalent bonds are broken, which is difficult to do. In another common allotrope, graphite, every carbon atom is covalently bonded to only 3 other carbon atoms, and the atoms are arranged in sheets that are not covalently bonded to each other. The sheets can be broken apart easily, ultimately meaning that graphite can be easily scratched. Coal is composed of particles of different allotropes of carbon, and some "amorphous carbon," which has no defined geometry in its atomic structure. Without a continuous network of covalent bonds, coal is easily scratched (i.e. it is not hard).
Answer:
The correct answer is - to make food for the seedling’s continued growth.
Explanation:
The true leaves that emerge from the seedlings are the leaves that are capable of performing photosynthesis and start generating food and energy. These support the plant for the rest of its life in terms of food and energy.
Seedlings grow from the soil, two leaves in beginning called cotyledons that are not the true leaves and not able to perform photosynthesis and generate their food for the seedling’s continued growth.
Natural selection is the differential survival and reproduction of individuals due to differences in phenotype. It is a key mechanism of evolution, the change in heritable traits of a population over time. The term "natural selection" was popularised by Charles Darwin who compared it with artificial selection, now more commonly referred to as selective breeding.
Answer:
C. primary cell wall → plasma membrane → cytoplasm → vacuole.
Explanation:
Every molecule or particle which enters into a cell, it must pass through several cellular structure at different level means it also depends on the type of molecule like size, shape, and nature (characteristics). On the surface of root cell, potassium ion pass through the primary cell wall which is most outer layer of plant cell, then it passes the second layer called plasma membrane, in the plasma membrane cytoplasm is present and when potassium ion reaches the cytoplasm then it will enter into the vacuole present in cytoplasm.
