Cell Division/Reproduction and blood types

 Lecture 3 Cell Division/Reproduction and blood types

Cell Division

Process of dividing a parent cell into two daughter cells. It is part of cell cycle in which the cell grows and replicates its chromosomes before division.

Cell division in prokaryotes happens through binary fission(Asexual reproduction). 

Two types of cell division in eukaryotes-

Hayflick Limit- Somatic(non reproductive) cells can only divide upto a limit before they stop dividing(in human approximately 40-60 times) 

Reproduction 

Biological process by which new offspring are produced from their parents. Two forms of reproduction- asexual and sexual

Sexual reproduction is a biological process of creating a new organism by combining the genetic material of two organisms using meiosis cell division. 

Gametes- organism's reproductive cells, also referred to as sex cells.

Male gametes cell- sperm cell

Female gametes cell- Egg cell or Ovum

    (Male + Female) Gametes cells → Zygote

Monozygotic Twin- Identical twins develop from one zygote(1 zygote → 2 Embryos) connected with shared Placenta

Dizygotic Twin- Twins develop from two different zygote connected with different Placenta

Male- XY chromosome,  Female- XX chromosome

In reproduction one chromosome of male combined with one chromosome of female

Male + Female – (Reproduction) → X(male)X(Female)   daughter

Male + Female – (Reproduction) → Y(male)X(Female)   son

3 Parents baby(mitochondrial replacement therapy)- The nucleus is removed from a donor egg cell and replaced by parents(Father-Mother) fertilized cell nucleus. This therapy is used to treat the defective mitochondria of mother cell. 

Types of Fertilization

• In Vivo Fertilizationt(IVF)- Process of fertilisation(egg + sperm) take place in vivo(living things). 
• In Vitro Fertilizationt(IVF)- Process of fertilisation(egg + sperm) take place in vitro(glass). Later the developed embryos is transferred into uterus. 

Assisted Reproductive Technology(ART)

Medical procedures used primarily to address infertility using in vitro fertilization(IVF), intracytoplasmic sperm injection(ICSI), cryopreservation of gametes or embryos, fertility medication, surrogacy etc. ART procedures are open to married couples, single women and also foreigners.

Features of ART Act 2021

• Regulate ART clinics and devices
• Act excludes unmarried men, divorced men, widowed men, unmarried yet cohabiting heterosexual couples, trans persons and homosexual couples from availing ART services.
• Setup National Assisted Reproductive Technology and Surrogacy Board.
• Men(<55 years), women(<50 years) 
• Donar man(21-55 years) Donor woman(23-35 Years) 
• A woman can donate only once(Upto 7 eggs) 

Surrogacy- In surrogacy, a woman(Surrogate mother/gestational carrier) agrees to carry and deliver a baby for another individual or couple, known as the intended parents.

Types of surrogacy

• Traditional Surrogacy- father's sperm to fertilise the surrogate's egg.
• Gestational Surrogacy- baby is not biologically related to the surrogate. Only surrogate's uterus used to carry baby. 

Surrogacy agreement

• Altruistic Surrogacy- surrogate mother does not receive financial compensation beyond reimbursement for medical expenses and other related costs.
• Commercial Surrogacy- surrogate mother receives financial compensation beyond just reimbursement for medical expenses and other costs associated with the pregnancy.

Surrogacy in India- Surrogacy Act 2021 allows altruistic surrogacy for couples with proven infertility or disease. Surrogacy is allowed for only Indian married couples+ Divorced/widowed woman. 

Eligibility criteria(Surrogacy Act 2021)-

• Couple must married for at least 5 years.
• Not any living child except children with disabilities or life-threatening disorders.
• Husband age- 26-55 years, wife age 25-50 years
• Surrogate mother(25-35 years) must be married with at least one child of her own. She must be a close relative of intending couple and not have been a surrogate mother earlier
• own gametes(if Partner have healthy egg and healthy sperm) 
• an egg or sperm of a donor(if one of the partners is suffering from a medical condition).
• Widowed/divorced woman(own egg with donor sperm) 
• No surrogacy(if both partners have medical issues). 

Blood Group

Classification of blood based on the presence and absence of antibodies and antigens on the surface of red blood cells(RBCs). Antibody in blood resist the acceptance of different blood group. 

Antigens can be proteins, peptides, polysaccharides, lipids or nucleic acids.

ABO blood group system

Apart from ABO blood group there are many rare blood group that are different from ABO blood group system. One of them is bombay blood group. 

Bombay blood group- The Bombay Blood or hh blood group is a rare blood phenotype first discovered in Mumbai in 1952 by Dr Y.M. Bhende. This blood phenotype is mostly found in India, Bangladesh, Pakistan and in some parts of the Middle East region. Bombay blood group can donate blood to ABO blood group but can't receive blood from them. 

Parent-Child blood group

Parent with blood group A can contribute- A antigen Or No Antigen

Parent with blood group B can contribute- B antigen Or No Antigen

So Parents with A and B blood group respectively can have children of blood group- O, A, B and AB

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