Tumor & Cancer – What is the Difference?

Tumor & Cancer – What is the Difference?

In this post we will clear our doubts regarding the term tumor and cancer. The general misconception what I have noticed is, when we hear the term tumor we think it is a cancer. But in fact tumor does not necessarily mean cancer.

Tumor aka neoplasm (neo = new and plasma = formation) is an abnormal mass of a tissue due to the abnormal growth. As a result, at that particular site lump appears which is called tumor. It is not necessary that all the tumors are cancerous. Let’s try and understand it.

Tumors are of two types:

1. Benign tumors:

Benign tumors are “non-progressive”. This means benign tumors limit their growth to a particular site wherever they are formed in the body. It is not going to spread form this site to any other site in the body. It cannot metastasize which means it cannot spread anywhere else in the body. Therefore, such benign tumors are noncancerous and they can be removed by surgery.

2. Malignant tumors:

Malignant tumors are cancerous because they have the ability to metastasize. They can spread from its primary site to any other part of the body.

Therefore, when a tumor is detected, it is very important to do biopsy to understand whether it is a benign tumor or malignant tumor.

Cancer is the term used to describe an uncontrolled growth of a cell. It is not necessary that all cancers are characterized by appearance of tumor. For example, blood cancer.

Cancer is a malignant condition. Based on what type of cancer or what stage it is detected, surgery, radiation therapy or chemotherapy is given.

Therefore, the term tumor and cancer cannot be used as synonyms.

I hope this post helped 🙂

To understand more in details, watch a video on this topic here.

Enzymes Involved in DNA Replication of Prokaryotes

Enzymes Involved in DNA Replication of Prokaryotes

DNA Replication in prokaryotes is one of the most important topics. To understand the whole basic mechanism of replication; there is this one thing I always felt while studying that would have been great if I find a list of all the enzymes involved in the process in order. So I tried and made my list which really helped me, especially during exam for quick revision. In this post I am sharing the list of enzymes involved in DNA replication of prokaryotes.

Sr. No. Enzyme Involved Key Role
1. Dna A Recognizes and binds to Ori C
2. Dna C Loads Dna B
3. Dna B (Helicase) Breaks the H-bonds between two DNA strands
4. SSB Protein (Single Stranded DNA Binding Protein) Prevents ssDNA from re-forming a double helix
5. Topoisomerase II (Gyrase) Removes topological stress
6. Dna G (Primase) Synthesizes primers
7. DNA Pol. III Synthesizes new strands of DNA in 5’à3’ direction
8. DNA Pol. I Removes primers (has exonuclease activity)

Fills the gap created (has polymerase activity)

9. DNA Ligase Seals the gap by formation of phosphodiester bond
10. Topoisomerase IV Separates DNA catenanes

I hope this post helps 🙂

To understand more in details about the DNA replication process in prokaryotes, watch a video on this topic here.