Answer:
The carbon atom has unique properties that allow it to form covalent bonds to as many as four different atoms, making this versatile element ideal to serve as the basic structural component, or “backbone,” of the macromolecules.
All living things contain carbon in some form. Carbon is the primary component of macromolecules, including proteins, lipids, nucleic acids, and carbohydrates. Carbon's molecular structure allows it to bond in many different ways and with many different elements.
Explanation:
Different structures and functions of roots
Explanation:
Roots are the underground descending non-green part of the plant.
Root functions: Anchorages the plant to the soil, absorbs water and nutrients from the soil.
Characteristics: Positively geotropic and hydrotropic, negatively phototropic; does not have nodes, internodes or stems.
Types:
- Tap root
- Adventitious root – fibrous, foliar and true adventitious roots
Structure and functions:
- Root cap or Calyptra: Cap-like structure covering the root tip
.
- Function: protects the meristematic tissues of the root, secretes mucilage which enhances the root tips to grow into the hard soil.
- Meristematic zone or growing point sub-terminal behind root cap. These cells are inverted and looks like a dome.
- Function – helps in the root growth by adding new cells to the root tip and other basal regions
- Zone of elongation behind the meristematic zone.
- Function – helps in elongation of the root
- Root hair zone: This is the zone of differentiation where cells differentiate into vascular tissues like phloem, xylem, endodermis, cortex etc.
- The main function of root hair is to increase the total surface area of root to facilitate more absorption of water and other nutrients from the soil
- Zone of maturation: the major and mature portion of a root.
- Function - lateral roots originates from this zone and radial differentiation leads to secondary growth.
<span>The Answer is D. Maintaining Structure</span>
<span>1) Which of
the following is a possible formula unit? PbO - Li2B - Al2Pb3
- ClO
The correct answer is PbO which is Lead(II) oxide – also known as Lead Monoxide
– which is an inorganic compound. It is an Amphoteric oxide which can be found,
in modern use, in industrial glass, ceramics, or computer components, due to
its crystal structure. </span>
<span>
</span>
<span>2) What is
the formula of a compound formed between iodine (I) and calcium (Ca)?
Calcium will always give two electrons. but iodine can receive only one. Therefore
two atoms of iodine react with one atom of calcium to give CaI2. Their bond is
an ionic bond.
Ca 2+ + 2I 1- --> CaI2</span>
<span>
</span>
<span>3) What is
the resulting formula unit when strontium (Sr) and phosphorus (P) bond?
Strontium (Sr) wants to lose two (2) electrons, and phosphorus (P) wants to
gain three (3). By using the criss-cross method, if you flip the 2 and 3 to the
opposite elements, you will end up with the formula Sr3P2.</span>
