As a Body Cell Grows Larger the Ratio of

This page tells you lot about how normal cells and tissues grow. You tin read data about

Cells and tissues

Our bodies are fabricated upward of about a hundred million million (100,000,000,000,000) tiny cells. You can only come across them nether a microscope.

Cells group themselves together to make up the tissues and organs of our bodies. They are a bit like building blocks. The diagram below shows what cells await like when they are grouped together.

Different types of body cells make up the different types of torso tissues. For instance, in that location are os cells in bone and breast cells in the breast.

There are more 200 different types of cells in the body.

Yous can read about different types of cells and cancer.

How torso tissues grow

Body tissues grow by increasing the number of cells that make them upwards. Cells in many tissues in the body dissever and grow very apace until we become adults.

When we are adults many cells mature and become specialised for their particular chore in the body. So they don’t make copies of themselves (reproduce) so often. Only some cells, such every bit peel cells or blood cells are dividing all the time.

When cells get damaged or die the torso makes new cells to supersede them. This process is called prison cell division. Ane cell doubles past dividing into two. Two cells go four then on. The diagram below shows cells dividing.

It seems that homo cells can reproduce up to 50 or 60 times at most. Then they usually die.

Stalk cells

Stem cells provide a puddle of dividing cells that the body uses to restock damaged or quondam cells.Stem cells are a kind of ‘starter cell’. They have the potential to develop into unlike cell types in the body.

When a stem cell multiplies, the resulting cells may remain equally stem cells. But under the right conditions, they become a type of jail cell with a more specialised part. For instance a muscle cell,


red blood prison cell


or brain cell.

Stem cells occur in the body in various places and stages during our lifetime. In the embryo, they requite rise to all the dissimilar tissues and organs of the body.

In adults each type of stem cell is ordinarily only able to develop into a few specific types of cell. For instance, adult stem cells in the bone marrow, known as haematopoietic stem cells, usually just requite ascension to dissimilar types of blood prison cell.

Cancer stem cells

Scientists now believe that stem cells might play a role in the development of cancer. They think that some tumours develop from faulty stem cells. This has led to the idea of cancer stem cells, which scientists have now identified in a range of cancer types. The types include bowel, breast and prostate cancer too equally leukaemia.

Researchers are looking at whether some treatments could target cancer stem cells.

How cells grow and divide

When cells divide and abound they do this very precisely and then that the new cells are exactly the same equally the old ones.

Each cell makes copies of all its genes. And then each cell splits into 2 with one set of genes in each new jail cell. During the process, there are lots of checks to make sure that everything has copied correctly. Only sometimes mistakes happen, which can lead to cancer.

You can read about genes and cancer on the page about how cancer starts.

This one minute video shows how healthy cells divide.

View a transcript for the video about how healthy cells dissever.

After dividing, the new cells rest for a while so they may divide once again if needed. The cells deport on doing this until they take fabricated plenty cells.

The cell cycle

To divide, the cell goes through a procedure called the jail cell cycle. At that place are 4 master stages or phases.

• Gap i or G1 phase, where the prison cell grows in size, and checks that everything is OK for it to divide.
• Synthesis or the S phase, where the cell copies its Deoxyribonucleic acid.
• Gap 2 or G2 phase, where the cells check that all its Deoxyribonucleic acid has been correctly copied.
• Mitosis or M phase, where the cell finally divides in two.

 The diagram beneath shows mitosis or Thousand phase.

During mitosis, the prison cell shares the copied Deoxyribonucleic acid as between the ii new cells. This ways that the prison cell separates all the copied chromosomes into 2 total sets. One at each end of the cell that is splitting in ii.

The other material that makes up the cell too splits in 2. The effect is two identical daughter cells.

How cells stop growing

Normal growth and healing is well ordered and precise. The cells know when:

• there are enough new cells to heal a cut
• a structure such as a finger is fully grown

Cells ship chemical letters to each other then that they cease growing and dividing when growth or healing is complete. The diagram below shows this happening.

How cells stay in the right identify

Cells in the body have a natural ability to stick together in the right place. This is so that the tissues and structures of the body course in the correct style. This is  called cell adhesion or ‘stickiness’.

Molecules on the surface of the cell friction match those on its neighbours. It is a bit like having a postcode. The lawmaking makes information technology very hard for the jail cell to move to the wrong place. But if the cell does find itself in a place where its postcode is unlike from its neighbours, it dies.

How cells dice

When cells go damaged or worn out, they cocky destruct. This is called apoptosis. It helps to protect us from developing cancer. Cells tin can also undergo apoptosis if they have broken away from their proper place in the trunk.

Scientists are doing a lot of work on apoptosis. If they tin can sympathise what makes a cell self destruct, they might be able to employ this to develop cancer treatments in the future.

How cancer cells and normal cells are different

Cancer cells are different from normal cells in a number of very of import means.

Find information well-nigh how cancer cells are different on the folio about cancer cells.