how many types of cell are there

Class 8 Question

By Preeti Awa · Jun 29, 2017 ·Class 8
23 Answers
Priyanshu Intelligent answered Sep 25, 2019
Cells are of two types: eukaryotic, which contain a nucleus, and prokaryotic, which do not. Prokaryotes are single-celled organisms, while eukaryotes can be either single-celled or multicellular.

Prokaryotic cells

Prokaryotes include bacteria and archaea, two of the three domains of life. Prokaryotic cells were the first form of life on Earth, characterised by having vital biological processes including cell signaling. They are simpler and smaller than eukaryotic cells, and lack membrane-bound organelles such as a nucleus. The DNA of a prokaryotic cell consists of a single circular chromosome that is in direct contact with the cytoplasm. The nuclear region in the cytoplasm is called the nucleoid. Most prokaryotes are the smallest of all organisms ranging from 0.5 to 2.0 µm in diameter.[12]

A prokaryotic cell has three architectural regions:

Enclosing the cell is the cell envelope – generally consisting of a plasma membrane covered by a cell wall which, for some bacteria, may be further covered by a third layer called a capsule. Though most prokaryotes have both a cell membrane and a cell wall, there are exceptions such as Mycoplasma (bacteria) and Thermoplasma (archaea) which only possess the cell membrane layer. The envelope gives rigidity to the cell and separates the interior of the cell from its environment, serving as a protective filter. The cell wall consists of peptidoglycan in bacteria, and acts as an additional barrier against exterior forces. It also prevents the cell from expanding and bursting (cytolysis) from osmotic pressure due to a hypotonic environment. Some eukaryotic cells (plant cells and fungal cells) also have a cell wall.

Inside the cell is the cytoplasmic region that contains the genome (DNA), ribosomes and various sorts of inclusions.[3] The genetic material is freely found in the cytoplasm. Prokaryotes can carry extrachromosomal DNA elements called plasmids, which are usually circular. Linear bacterial plasmids have been identified in several species of spirochete bacteria, including members of the genus Borrelia notably Borrelia burgdorferi, which causes Lyme disease.[13] Though not forming a nucleus, the DNA is condensed in a nucleoid. Plasmids encode additional genes, such as antibiotic resistance genes.

On the outside, flagella and pili project from the cell's surface. These are structures (not present in all prokaryotes) made of proteins that facilitate movement and communication between cells.

Eukaryotic cells

Plants, animals, fungi, slime moulds, protozoa, and algae are all eukaryotic. These cells are about fifteen times wider than a typical prokaryote and can be as much as a thousand times greater in volume. The main distinguishing feature of eukaryotes as compared to prokaryotes is compartmentalization: the presence of membrane-bound organelles (compartments) in which specific activities take place. Most important among these is a cell nucleus,[3] an organelle that houses the cell's DNA. This nucleus gives the eukaryote its name, which means "true kernel (nucleus)". Other differences include:

The plasma membrane resembles that of prokaryotes in function, with minor differences in the setup. Cell walls may or may not be present.

The eukaryotic DNA is organized in one or more linear molecules, called chromosomes, which are associated with histone proteins. All chromosomal DNA is stored in the cell nucleus, separated from the cytoplasm by a membrane.[3] Some eukaryotic organelles such as mitochondria also contain some DNA.

Many eukaryotic cells are ciliated with primary cilia. Primary cilia play important roles in chemosensation, mechanosensation, and thermosensation. Each cilium may thus be "viewed as a sensory cellular antennae that coordinates a large number of cellular signaling pathways, sometimes coupling the signaling to ciliary motility or alternatively to cell division and differentiation."[14]

Motile eukaryotes can move using motile cilia or flagella. Motile cells are absent in conifers and flowering plants.[15] Eukaryotic flagella are more complex than those of prokaryotes.[16]

Angel answered Feb 13, 2019
200 ᴛʏᴘᴇs ᴏғ ᴄᴇʟʟ ᴀʀᴇ ғᴏᴜɴᴅ ɪɴ ᴏᴜʀ ʙᴏᴅʏ.

Tʜᴇʀᴇ ᴀʀᴇ ᴛᴡᴏ ᴛʏᴘᴇs ᴏғ ᴏʀɢᴀɴɪsᴍ -:

*ᴜɴɪᴄᴇʟʟᴜʟᴀʀ - Tʜᴇ sɪɴɢʟᴇ ᴄᴇʟʟᴇᴅ ᴏʀɢᴀɴɪsᴍ ᴀʀᴇ ᴄᴀʟʟᴇᴅ ᴜɴɪᴄᴇʟʟᴜʟᴀʀ .ғᴏʀ ᴇxᴀᴍᴘʟᴇ -ᴀᴍᴏᴇʙᴀ.

*ᴍᴜʟᴛɪᴄᴇʟʟᴜʟᴀʀ -Tʜᴇ ᴏʀɢᴀɴɪsᴍ ʜᴀᴠɪɴɢ ᴍᴏʀᴇ ᴛʜᴀɴ ᴏɴᴇ ᴄᴇʟʟ . ғᴏʀ ᴇxᴀᴍᴘʟᴇ -ʜᴜᴍᴀɴ ʙᴇɪɴɢs ᴀɴᴅ ᴀɴɪᴍᴀʟs

Ankita Choudhary. answered Nov 23, 2018
200 type of cell r found in our body......and 20 different

type of structure ...

Sonal Sinha answered Nov 21, 2018
In human body , there are about 200 types of cell and 20 different types of structure or organless.

Raiyan Zaib answered Jun 08, 2020
The human body? There are about 200 different cell .

Scientists concluded that the average human body contains approximately 37.2 trillion cells! Of course, your body will have more or fewer cells than that total, depending upon how your size compares to the average human being, but that's a good starting point for estimating the number of cells in your own body!

Tajing Jomyang answered Jun 09, 2020
200 different type of cells

Sakshi answered Sep 25, 2019
Two types.
1. prokaryotic cells.
2. eukaryotic cells.

Subhash Saini answered Jun 29, 2017
Your body has many different kinds of cells. Though they might look different under a microscope,most cells have chemical and structural features in common .In humans,there are about 200 different types of cells,and within these cells there are about 20 different types of structure or organelles.

Nyan Leembu answered May 20, 2020
200 type of cell in our body.

Ammu Baby answered Oct 27, 2019
So many types ,for example (redmi,micromax,Samsung,techno pro etc..)

Neetu Pandey answered 2 weeks ago
Cells are of 2 types
prokaryotes and eukaryotes
prokaryotes are single celled whereas eukaryotes are multicellular.

Sahil Varma answered Feb 13, 2019
What is cell called the strctural and function unit of life? in 4marks

D Dhanush answered Aug 15, 2020
There are over 200 different cells types in human body

Elango D answered Jun 08, 2020
In our body there are 200 different types of cells.And of 20 different types of structure

Jayakrushna Giri answered May 28, 2020
Two types of cells are present in our body.
That is
1.eucaryotic cell
2.prokaryotic cell

Mansi Patil answered Sep 25, 2019
There are two types of cell:-
1) Prokaryotic cell
2)Eukaryotic cell

Then Eukaryotic cell dividend into two parts
1) Multicellular

Chandra Sekhar Maharana answered Aug 17, 2019
Biology: there is 2 types of cells.
unicellular and multicellular
physics: there are 2 types of cells
dry cell and wet cell

Manju Maurya answered Dec 10, 2019
On which basis do you want to categories?

Ajay Mohta answered Jun 07, 2020
200 different types

Your body has many different kinds of cells. Though they might look different under a microscope, most cells have chemical and structural features in common. In humans, there are about 200 different types of cells, and within these cells there are about 20 different types of structures or organelles.

Srujana Gowda answered 23 hours ago
According to number of cells,they are classified as:
• Unicellular : Organisms whose body consists of a single cell.
• Multicellular : Organisms whose body consists of many cells.
According to the presence of nucleus,they are classified as:
• Prokaryotes : Meaning of Prokaryotes : Pro means Before nucleus. It means that Prokaryotes have the absence of nucleus.
• Eukaryotes : Meaning of Eukaryotes : True nucleus.
It means that Eukaryotes have the presence of nucleus.

Krishna Kashyap answered Dec 10, 2019
There are two types of cell-i)Prokaryotic ii)Eukaryotic

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