CBSE > Class 08 > Science | CBSE Board | Homework Help

A metal is an element that readily forms positive ions (cations) and has metallic bonds. Metals are sometimes described as a lattice of positive ions surrounded by a cloud of delocalized electrons.

A metal is a material (an element, compound, or alloy) that is typically hard, opaque, shiny, and has good electrical and thermal conductivity.Examples:copper,iron etc. ‎

1Thank You

ANSWER

With the help of example,show the variation in shape and size of the cell

Posted by Surya Duth 8 years, 3 months ago

CBSE > Class 08 > Science

0 answers

ANSWER

Why Questions are out of text books?

Posted by Ronith Goudar 8 years, 3 months ago

CBSE > Class 08 > Science

1 answers

Radhika Duggal 8 years, 3 months ago

To give you more knowledge

1Thank You

ANSWER

Who man had made artificial fibre

Posted by Kaushik Sharma 8 years, 3 months ago

CBSE > Class 08 > Science

0 answers

ANSWER

National parks of Karnataka

Posted by Srushti Srushti 8 years, 3 months ago

CBSE > Class 08 > Science

1 answers

Abhijeet Padghan 8 years, 3 months ago

Satya

1Thank You

ANSWER

When is sound loud

Posted by Aditya Prakash 8 years, 3 months ago

CBSE > Class 08 > Science

1 answers

Amar Kumar 8 years, 3 months ago

Noise levels are measured in decibels, known as dB. Loud noises have high decibel levels. You can listen to sounds at levels from 0-70 dB for as long as you want. Sounds louder than 85 dB may cause damage if you listen for 8 hours or more. Researchers have found that people who are exposed over long periods of time to noise levels at 85 decibels or higher are at a much greater risk for hearing loss.

0Thank You

ANSWER

Explain why LPG is chemical change

Posted by Md Danish 8 years, 3 months ago

CBSE > Class 08 > Science

0 answers

ANSWER

A defenition for sound

Posted by Elwin Thomas 8 years, 3 months ago

CBSE > Class 08 > Science

1 answers

Amar Kumar 8 years, 3 months ago

Sound:Vibrations transmitted through an elastic material or a solid, liquid, or gas, with frequencies in the range of 20 hertz to 20,000 hertz, capable of being detected by human organs of hearing.

Sound is defined as a oscillation in pressure, stress, particle displacement, particle velocity, etc., propagated in a medium with internal forces (e.g., elastic or viscous), or the superposition of such propagated oscillation.

1Thank You

ANSWER

Define pathogens

Posted by Kishor Garandwal 8 years, 3 months ago

CBSE > Class 08 > Science

2 answers

Ann Mary Joseph Joseph 8 years, 3 months ago

Disease causing microbes are called pathogens

1Thank You

Amar Kumar 8 years, 3 months ago

Pathogen: An agent that causes infection or disease, especially a microorganism, such as a bacterium or protozoan, or a virus.

1Thank You

ANSWER

State five difference between eukaryotic cell and prokaryotic cell

Posted by Souvik Panda 4 years, 7 months ago

CBSE > Class 08 > Science

1 answers

Sia ? 4 years, 7 months ago

	Prokaryotes	Eukaryotes
Type of Cell	Always unicellular	Unicellular and multi-cellular
Cell size	Ranges in size from 0.2 μm – 2.0 μm in diameter	Size ranges from 10 μm – 100 μm in diameter
Cell wall	Usually present; chemically complex in nature	When present, chemically simple in nature
Nucleus	Absent. Instead, they have a nucleoid region in the cell	Present
Ribosomes	Present. Smaller in size and spherical in shape	Present. Comparatively larger in size and linear in shape
DNA arrangement	Circular	Linear
Mitochondria	Absent	Present
Cytoplasm	Present, but cell organelles absent	Present, cell organelles present
Endoplasmic reticulum	Absent	Present
Plasmids	Present	Very rarely found in eukaryotes
Ribosome	Small ribosomes	Large ribosomes
Lysosome	Lysosomes and centrosomes are absent	Lysosomes and centrosomes are present
Cell division	Through binary fission	Through mitosis
Flagella	The flagella are smaller in size	The flagella are larger in size
Reproduction	Asexual	Both asexual and sexual
Example	Bacteria and Archaea	Plant and Animal cell