Download App

Human Health and Disease — BIOLOGY STD 12 Science — Question

Gujarat BoardEnglish MediumSTD 12 ScienceBIOLOGYHuman Health and Disease3 Marks
Question
Differentiate between T-helper cells and T-killer cells.
✓

Answer

Differences between T-helper cells and T-killer cells :
S.No.T-Helper cellsT-killer cells
1These cells secrete interleukins and activate T-killer cells and sensitized T-cells.Whereas these cells, after coming in contact with the micro-organism, secrete a cytotoxic substance directly from the body of the micro-organism and destroy it.
2These stimulate macrophages to perform cytophagic action. AIDS virus paralyzes the immune system by inactivating or destroying these cells.These killer cells also consume tissue cells infected with viruses.

Need a full question paper?

Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.

Start Generating Free

Explore more

More "3 Marks Question" from Human Health and Disease→Human Health and Disease — all question types→BIOLOGY STD 12 Science question papers→Gujarat Board STD 12 Science question papers→Gujarat Board question paper generator→

Similar questions

Name and explain the surgical method advised to human males and females as a means of birth control. Mention its one advantage and one disadvantage.
→
  1. Write the palindromic nucleotide sequence for the following DNA segment:
5' - GAATTC - 3'
  1. Name the restriction endonuclease that recognises this sequence.
  2. How are 'sticky ends' produced? Mention their role.
→
Which causative organisms are responsible for ringworm? List any two symptoms of the disease.
→
Expand 'BAC' and 'YAC'. Explain how they were used in sequencing of human genomes.
→
Since October 02, 2014 'Swachh Bharat Abhiyan' has been launched in our country.
  1. Write your views on this initiative giving justification.
  2. As a biologist name two problems that you may face while implementing the programme in your locality.
  3. Suggest two remedial methods to overcome these problems.
→
Explain how biomagnification of DDT occurs in an aquatic food chain.
→
Both Down’s syndrome and Turner’s syndrome are examples of chromosomal disorders. Cite the differences between the two.
→
How cancer is detected and diagnosed?
→
  1. What are meiocytes?
  2. If the chromosome number in meiocytes of human beings, housefly, potato, apple, dog and maize are 46, 12, 48, 34,78 and 20, respectively. What will be the chromosome numbers in gametes of these species?
→
Study the population growth curves in the graph given below and answer the questions which follow:
  1. Identify the growth curves ‘a’ and ‘b'.
  2. Which one of them is considered a more realistic one and why?
  3. If dN/dt=rN(K-N/K) is the equation of the logistic growth curve, what does K stand for?
  4. What is symbolised by N?
→