22.3 Cloning in animals Flashcards
in which animal is natural animal cloning more common in?
invertebrates
what is the main form vertebrate cloning?
formation of monozygotic twins
how are monozygotic twins formed?
the embryo splits to form 2 separate embryos
what are the 2 methods of artificial animal cloning?
artificial embryo twinning
somatic cell nuclear transfer
how does artificial embryo twinning work?
the early embyro is manually split to form 2 or more foetuses
why is articial twinning done by the farming community?
used to produce the maximum offspring from cattle
what is the first stage of artificial twinning?
a cow with the desirable characteristics is treated with hormones which causes it to super ovulate and produce more mature ova
what is the second stage of artificial twinning?
the ova is fertilised either naturally or by insemination to produce an embryo
then the early embryos are removed from the uterus
what is the third stage of artificial twinning?
the early embryos are then split to produce several smaller embryos on a petri dish
what is the fourth stage of artificial twinning?
the split embryos are grown in the lab for a few days before being implanted in different surrogate mother
what is the final stage of artificial twinning?
the embryos develop into foetuses and then born naturally by the surrogate mothers
artifical twinning summary
artificial twinning summary
what is SCNT?
somatic cell nuclear transfer
what is a somatic cell?
any cell not involved in reproduction
what is the first stage of SCNT?
nucleus is removed from a somatic cell of an adult animal
what is the second stage of SCNT?
the nucleus is removed from mature egg cell from a different female animal
this cell is now enucleated
what is the third stage of SCNT?
the nucleus from the adult somatic cell is placed in the enucleated ovum and then a shock is produced causing fusion snd then division
what is the fourth stage of SCNT?
the embryo develops and is then tranferred into uteris of a surrogate animal
what is the final stage of SCNT?
the surrogate gives birth to animal which is a clone of the animal which gave the somatic cell nucleus
how can SCNT be used?
used in pharming
used to produce GM animals which grow organs used for human transplants
what is pharming?
production of animals which have been genetically engineered to produce human proteins in their milk
what are the main uses for animal cloning?
research purposes
agriculture
clone genetically-engineered animals
save animals from extinction
research purposes
by cloning an animal, the effects of drugs can be seen by testing drugs on a cloned animal and comparing with the original
agriculture
cloning can be used to increase the number of animals with desirable characteristics
clone genetically-engineered animals
used to increase the number of genetically modified animals to produce a specific substance
save animals from extinction
by cloning an endangered animal, you increase their population which allows them to reproduce
advs for animal cloning
- allows for high-yield farming with animals able to produce more offspring
- increases success of desired gene being passed on to offspring
- animals can be cloned for performance reasons
- rare or endangered species of animal can be reproduced to increase numbers
disv for animal cloning
- SCNT is inefficient as it requires many eggs for it to be successful
- many deformed embryos are produced = waste ETHICAL ISSUE
- clones normally have a shortened lifespan
- hasnt actually been successful in increasing the population of endangered species
