Ib Biology 4.4 Biotechnology

Front 1

What is PCR (polymerase chain reaction) used for?

Back 1

to copy and amplify tiny quantities of DNA. Very useful if you only have a small sample of DNA (like from a blood sample from a patient or a crime scene) and you need lots of DNA to do DNA profiling.

Front 2

How does gel electrophoresis work?

Back 2

Gel electrophoresis is used to separate DNA (or other molecules) by theis size and charge. The DNA fragments move in an electric field. The negatively charged DNA all moves towards the positive electrode. Small pieces move farther than large pieces.

Front 3

What biotechnology applications is gel electrophoresis useful for?

Back 3

DNA profiling

Front 4

Which electrode (positive or negative) will DNA travel towards in gel electrophoresis? Why?

Back 4

positive electrode; DNA is negatively charged (think of all of those phosphate groups!). Note that if the electrodes are not labelled in a gel

Front 5

What are the outcomes of the complete sequencing of the human genome?

Back 5

knowledge of the number of human genes

Front 6

What property of the genetic code makes it possible for a gene to be transferred between species?

Back 6

The genetic code is universal

Front 7

Outline the basic technique used for gene transfer.

Back 7

mRNA is extracted from the organism with the gene you want use; a DNA copy is made of the RNA using reverse transcriptase; "sticky ends" are added to the DNA copy; the plasmid is cut with restriction enzymes to create sticky ends; the gene (like insulin) and the plasmid DNA are mixed together (the sticky ends will stick together); DNA ligase seals the plasmid together; transformation of the host cell (bacteria

Front 8

What does reverse transcriptase do?

Back 8

make DNA from an RNA template; used in gene transfter and by retroviruses (including HIV/AIDS)

Front 9

What does DNA ligase do?

Back 9

covalently links pieces of DNA; used in gene transfer and DNA replication

Front 10

Give 2 examples of genetically modified crops or animals

Back 10

IB's examples: salt tolerance gene in tomato plants; sysnthesis of beta-carotene gene in rice; herbicide resistance genes in crop plants; factor IX (human blood clotting gene) in sheep milk. Others may be acceptable.

Front 11

What are the potential benefits of genetic modification

Back 11

Less expensive food

Front 12

What are the potential harmful effects of genetic modification

Back 12

Possibility of allergies in human foods; If genetically engineered organisms are released into the environment they could out-compete naturally occurring varieties

Front 13

Define clone

Back 13

a group of genetically identical organisms or a group of cells derived from a single parent cell

Front 14

Outline a technique for cloning using differentiated animal cells

Back 14

remove nucleus from a somatic (non-reproductive) cell from an adult organism; remove nucleus from an egg cell; transfer the nucleus from adult cell into the egg cell; implant the egg with the new nucleus into a host mother; the baby clone will be genetically identical to the adult donor that the nucleus came from. his process is called somatic nuclear transfer.

Front 15

What is therapeutic cloning?

Back 15

creation of embryos to supply embryonic stem cells for medical use

Front 16

What are the ethical issues of therapeutic cloning in humans?

Back 16

Pro: 1. Create therapies that save lives and reduce suffering