Event In sexual Reproduction : Biology Blog

                                 Event In Sexual Reproduction 

Reproduction is defined as the process through which the parents can produce their offerings which may be morphologically and physiologically similar to them. There are two types of reproduction -

•   Asexual Reproduction  - An only single type of parent is responsible for producing offspring which is morphologically similar to their parents and known as Clone. 

Forms Of Asexual Reproduction

•   Sexual Reproduction - In this type of reproduction, both types of parents - male and female; are involved to produce offspring which is morphologically variable from their parents. 

There are three events of sexual reproduction -To know about events of sexual reproduction please click on this link below -

Pre fertilization 

Fertilization 

Post fertilization 

Biology 12th Class Question Bank : Part 3

                                            Sheet - 3

• What is Hardy Weinberg equation ?
• Explain ecological pyramid with examples .
• Write the silent feature of genetic code .
• Explain the process of DNA Fingerprinting .
• What are cry proteins ? name the organism that produce it .
• Explain Watson crick model of DNA .
• Explain gene therapy .
• What is golden rice .
• Describe the process involved in plant breeding .
   
• Explain Harshey and Chase experiment of DNA .
• What is totipotency ? explain micro propogation and somaclonal hybridization .
• Light on Darwin theory of evolution .
• Why is the offspring formed by asexual reproduction referred to as a clone ?
• Write the difference between asexual and sexual reproduction .
• An orchid plant is growing on the branch of mango tree . How do you describe the interaction between the orchid plant and the mango tree ?

Chromosomal Disorder's - Down Syndrome 12th Biology

                                      Down Syndrome 

Down syndrome is a type of genetic disorder first described by Langdon Down in 1866. This disorder is caused due to an extra copy of chromosome  21 in the developed embryo. Normally, the human chromosome contains 46 chromosomes out of which 22 are autosomes and the other one is sex cell.  In the process of fertilization,  the fertilized egg formed from the fusion of the sperm cell and egg cell contains a copy of 23 chromosomes but in some cases, an Trisomy 21. This trisomic condition is arisen due to the formation of n+1 male or female gamete by non-disjunction and the subsequent fertilization by a normal (n) gamete. 

Symptoms -

• Flat facial feature especially nose.
• almond eyes.
• Bulging tongue.
• Short neck.
• Big Palm.
• mental retardedness.
• Short height including child and adults. 

Diagnosis - There are two ways of diagnosing this syndrome.

                       

•  Amniocentesis  - A small quantity of amniotic fluid is taken from a pregnant mother and screening is done for various birth defects like a neural defect, down syndrome, etc.
  
  
•   Chorionic villus sample  - A small sample of placental cells is taken for screening the birth defects.

Related Blog -  Klinefelter Syndrome 

What is ZIFT procedure for Infertility | Biology Blog

                                               ZIFT 

Zygote Intra Fallopian Transfer is a type of assisted reproductive technology used to treat infertility problems in many women. The zygote is prepared in a laboratory and then placed into the Fallopian tube of a woman by a minor surgery called laparoscopy. This technique is also known as Tubal Embryo Transfer.                      

       

• ZIFT is very useful in the following cases - 
• Infertility Problem.                                    
•  low sperm count 
•  irregular periods  

Procedure -   It will take around five to six weeks for each cycle of ZIFT to complete the procedure. IVF & GIFT also has a similar procedure just like ZIFT but the only difference is that here the zygote is directly transferred into the fallopian tube of a woman through a minor surgery called Laparoscopy.

Let's see the step-by-step procedure for successful ZIFT.

• The ovary of the female is stimulated by medication so that the chances of getting multiple eggs are increased.
  
  
• In the meanwhile, you have to consult the doctor so that the progress of the follicles can be checked through ultrasound.
   
• The eggs are then collected through an aspiration method.
  
  
• These eggs are then combined with your spouse's sperm in the laboratory and monitored for fertilization. After fertilization,  a single-cell zygote is formed. 

• Afterward, the doctors perform surgery in the abdomen area of a female,  and the zygote is inserted into the fallopian tube through a laparoscope.
  
  
• If the transfer is successful then the chances of becoming pregnant are increases.
  
  
• The final step is to check the pregnancy for which the doctor performs a blood test and determines if pregnancy occurred or not .  

Frederick Griffith transformation experiment and conclusion

                                   Griffith Experiment

 Introduction -

1918 is the year of pandemic Influenza, the disease that was spread on a large scale over worldwide and killed a large population of the world. Influenza disease is that which spread through animals into a human. The scientist was studying the possibility of a vaccine for Influenza. In 1928 Fredrick Griffith's success in discovering the vaccine for neutralizing the virus.

Experiment -

 Fredrick Griffith had done the experiment for this. He conducted his experiment by using two strains of streptococcus  bacteria; one is type III -S (smooth ) which is virulent and type II -R (rough)  which is non-virulent.  Type III- S has capable of forming a capsule made up of sugar (polysaccharide) that helps to protect from the host immune system consequently the death of the host. Type II -R is not able to form a coating around the body and affected by the host immunity resulting in no death of the host.

Also, refer- Griffith experiment in Hindi

The whole experiment can be well understood by the figure -

Conclusion -  By doing his experiment he concluded that bacteria are capable of transforming genetic information by following the principle of transformation which can change them from one form to another form.

You may also like - Chargaff rule of DNA

Biology 12th Class Question Bank : part 2

                                         Sheet - 2 

1. Write about the four phases in  menstrual cycle and also explain the hormonal control of  this period .
2. Write the four way to transfer pollen grain on stigma ?
3. Explain industrial melanism .
4.  Explain Mendel law of independent assortment .
5.  Write the difference between GIFT & ZIFT .
6.  Write the full form of ART .
7.  Explain Post fertilisation event .
8.  Explain law of co dominance .
9.  Explain down syndrome .
10.  Describe Griffith Experiment .
11.  Explain the process of PCR .
12.  Explain HIV process in detail.
13.  What do you mean by Air pollution ? write the causes of air pollution .
14.  Why CNG is better than diesel ?
15.  What is green house effect ?