Question

Q1. Differentiate between:
(a) Rods and cones
(b) Regular and irregular reflection
(c) Electrolyte and non-electrolyte
(d) Noise and music
(e) Audible and inaudible sounds
(f) Contact and non-contact force
(g) Plant cell and animal cell
(h) Prokaryotes and eukaryotes
(i) Unicellular and multicellular
(j) Exhaustible and inexhaustible natural resources
(k) Thermoplastics and thermosetting plastics
(l) Monomer and polymer
(m) Manure and fertilisers

Answer 1

Answer:

Q1. Differentiate between:

(a) Rods and cones

Rods are responsible for vision at low light levels (scotopic vision). They do not mediate color vision, and have a low spatial acuity. Cones are active at higher light levels (photopic vision), are capable of color vision and are responsible for high spatial acuity.

(b) Regular and irregular reflection

In regular reflection, light reflected from a smooth surface in a definite direction. In irregular reflection, light reflected from a rough surface in all directions and not in a definite direction.

(c) Electrolyte and non-electrolyte

Electrolytes are salts or molecules that ionize completely in solution. As a result, electrolyte solutions readily conduct electricity. Nonelectrolytes do not dissociate into ions in solution; nonelectrolyte solutions do not, therefore, conduct electricity.

(d) Noise and music

Noise is sound with a continuous structure. Music is composed of sounds with a fundamental frequency and overtones. Noise is composed of sounds with frequencies that range continuously in value from as low as you can hear to as high as you can hear — not necessarily at equal intensity, however.

(e) Audible and inaudible sounds

Audible Sounds are the sounds of frequency which are audible to the human ear. The frequency of audible sounds is usually between 20Hzto20kHz. Inaudible sounds are the sounds of frequency which are not audible to the human ear. The frequency of inaudible sounds is below20Hzand greater than20kHz.

(f) Contact and non-contact force

A non-contact force is a force which acts on an object without coming physically in contact with it. ... In contrast a contact force is a force applied to a body by another body that is in contact with it.

(g) Plant cell and animal cell

Cells are the basic unit of a living organism and where all life processes are carried out. Animal cells and plant cells share the common components of a nucleus, cytoplasm, mitochondria and a cell membrane. Plant cells have three extra components, a vacuole, chloroplast and a cell wall.

(h) Prokaryotes and eukaryotes

Prokaryotes are organisms that consist of a single prokaryotic cell. Eukaryotic cells are found in plants, animals, fungi, and protists. They range from 10–100 μm in diameter, and their DNA is contained within a membrane-bound nucleus. Eukaryotes are organisms containing eukaryotic cells.

(i) Unicellular and multicellular

Unicellular organisms are made up of only one cell that carries out all of the functions needed by the organism, while multicellular organisms use many different cells to function. ... Multicellular organisms are composed of more than one cell, with groups of cells differentiating to take on specialized functions.

(j) Exhaustible and inexhaustible natural resources

Exhaustible Natural Resources are petrol, coal natural gas, forest and minerals. Inexhaustible Natural resources are wind, sunlight and water.

(k) Thermoplastics and thermosetting plastics

Thermoplastics have secondary bonds between molecular chains. Thermosetting plastics have primary bonds between molecular chains and held together by strong cross-links. Thermoplastics have low melting points and low tensile strength. Thermosetting plastics have high melting points and tensile strength.

(l) Monomer and polymer

Plastics always consist of large molecules called polymers. Polymers, in turn, consist of many identical small particles that are strung together like a chain. We call these individual small particles monomers. The length of these polymer chains determines the properties of plastic.