Biology unit 21 Flashcards
State about bacteria in biotechnology
bacteria are useful in biotechnology and genetic modification due to their rapid reproduction rate and their ability to make complex molecules.
Role of anaerobic respiration in yeast during the production of ethanol from biofuels
In yeast, anaerobic respiration primarily results in the fermentation of sugars. When oxygen is not available, yeast cells convert glucose into ethanol and carbon dioxide.
Equation: C6H12O6 ➡️ 2C2H5OH + 2CO2
The role of anaerobic respiration in yeast during ethanol production is as it serves as a sustainable/renewable energy source method for producing biofuels
Role role of anaerobic respiration in yeast during bread making
During anaerobic respiration, the yeast primarily converts glucose into ethanol and CO2. The CO2 produced gets trapped in the dough, causing it to rise and create a light, airy texture in the bread. While the ethanol produced is also a byproduct, it contributes to the flavor of the bread. However, most of the alcohol evaporates during baking.
Use of pectinase in fruit juice production
Pectinase is an enzyme used in fruit juice production to break down pectin (cell wall) It is added to crushed fruit pulp, then heated to activate the enzyme
Biological washing powders
Biological washing powders contain enzymes that help
quickly break down large molecules to smaller soluble molecules and are effective at lower temperatures, meaning less energy (and money) has to be used in order to wash clothes to get them clean
use of lactase to produce lactose-free milk
Milk can be made lactose free by adding the enzyme lactase to it and leaving it to stand for a while to allow the enzyme to break down the lactose
Describe genetic modification
As changing the genetic material of an organism by removing changing or inserting individual genes
Process of genetic modification part 1
Identify the gene of interest in
the original organism. The genome of
the original organism will likely need
to be sequenced to identify its
location. Use restriction enzymes to cut a gene from the original organism Restriction enzymes are a type of enzyme that cuts DNA. They will only cut the DNA at a specific sequence
When the restriction enzyme finds the correct sequence it will cut the dna leaving single stranded dna ends called sticky ends
Process of genetic modification part 2
A bacterial plasmid is cut by the same restriction enzyme leaving it with corresponding sticky ends.The plasmid and the isolated gene are joined together by DNA ligase enzyme
If two pieces of DNA have matching sticky ends. DNA ligase will link them to form a single, unbroken molecule of DNA.
Example of genetic modification part 1
The gene for human insulin has been inserted into bacteria which then produce human insulin which can be used for medical use for diabetes
Crop plants have been genetical modified to contain a gene from a bacterium that produces a poison that kills insects, making them resistant to insect pests.
Example of genetic modification part 2
Crop plants - resistant to certain herbicides, meaning that when the herbicide is sprayed on the crop it only kills weeds and does not affect the crop plant
Example of genetic modification part 3
improve nutritional qualities. eg ‘golden rice’ contains genes from another plant and a bacterium which make the rice grains produce a chemical that is turned into vitamin A in the human body.
Advantages of genetically modifying crops
- Reduced use of chemicals e.g herbicides and pesticides - better for the environment
- increased yield from the crops as they are not competing with weeds for resources of suffering from pest damage
Disadvantage of genetically modifying crops
- increased costs of seeds - companies that make GM seeds charge more for them to cover the cost of developing them, meaning smaller farmers cannot complete with larger farms.
Disadvantage of genetically modifying crops part 2
- risk of inserted genes being transferred to wild plants by pollination which could reduce the usefulness of the GM crops.
