SB4 Flashcards

Question

What are organisms that contain DNA from another organism called?

Answer 1

Transgenic.

Answer 2

GMO's (genetically modified organism) are organisms that had their DNA changed. This is done in order for the organisms to: 1. Produce certain substances (e.g. beta-carotene) 2. Have characteristics to allow to survive in different conditions (e.g. tomatoes not to freeze at extremely low temperatures)

Answer 3

1. Create golden rice to produce beta-carotene to be taken by humans (humans that lack beta-carotene cannot make Vit A which can cause blindness) 2. Create organisms that are resistant to disease-causing organisms 3. Create organisms faster and to be larger than normal so that they provide more yield to feed the growing population

Answer 4

The growing of cells or tissues in either a liquid with nutrients or in a special gel called agar with nutrients.

Answer 5

Stem cells can be found in plants and animals. They are unspecialised cells that can differentiate into other cells and form tissues.

Answer 6

First way is by using a piece of the plant: 1. Put the plant in bleach solution to sterilise it so that all the microorganisms such as bacteria die and won't compete with the plant for nutrients. 2. Place the piece of plant into a sterile agar (medium) that contains all nutrients needed for growth. 3. Add special hormones to the agar so that the plant develops shoots and roots. 4. Once the plant has grown enough then they plant them into soil or compost. Second way is by using plant cells: 1. Put the plant in bleach solution to sterilise it so that all the microorganisms such as bacteria die and won't compete with the plant for nutrients. 2. Take some cells and put them into a sterile medium so that they grow into a callus (a ball of unspecialised cells). 3. The callus will then develop plantlets. 4. Treat the plantlets with hormones so that it develops roots and shoots. 5. Take the plantlets and separate them and put them into a sterile medium so that they can grow. 6. Once the plants have grown enough, then they plant them into soil or compost.

Answer 7

1. Locate the gene that you want 2. Using restriction enzymes, cut the gene from the DNA 3. Remove a plasmid from a bacterium 4. Using the same restriction enzymes cut the plasmid open creating the sticky ends 5. Add the gene for that particular characteristic 6. Stick the gene on the plasmid using the enzyme DNA ligase 7. Put the plasmid back in the bacterium 8. Bacterium multiplies and also produces the protein of that gene

Answer 8

1. Only a few alleles are selected to be passed on to the next generation, so other alleles disappear and that leads to less variation. 2. If the organisms have very similar DNA and a condition changes (e.g. a disease strikes) they will all be susceptible to that disease and will all die. 3. Animal welfare: when animals suffer (e.g. if they are made to produce meat, they are too heavy to move)

Answer 9

1. Crop seeds are more expensive so poor farmers cannot afford to buy them. 2. Herbicide resistant crops can breed with weeds creating herbicide resistant weeds. This means when you spray the crops with herbicide, the weed will not die and will continue to compete with the crops for resources, causing the crop not to grow very much. 3. Some people believe that eating GM food is very unhealthy and will create problems.

Answer 10

Advantages: 1. Herbicide resistant/faster growth 2. Increased yield 3. Less use of chemical pesticides 4. Less harm to living organisms 5. Fix health problems (such as Vit A deficiency - by creating beta-carotene rice) Disadvantages: 1. Gene transfer due to cross pollination leading to superweeds 2. Greater competition between plant species 3. Reduction in biodiversity/non-target organisms are harmed 4. Long-term effects on human health/unknown side effects 5. Expensive to produce and buy 6. Have to rely on GM companies to buy (e.g. seeds)

Answer 11

Advantages: 1. Rapid population growth 2. Increased yield of product 3. Making insulin 4. No animals are harmed/used in production 5. Less side-effects 6. Suitable to be used by vegans Disadvantages: 1. Long-term effects on human health/unknown side effects 2. Expensive to produce and buy 3. Risks in culturing microorganisms

Answer 12

Advantages: 1. Production of hormones Disadvantages: 1. Long-term effects on human health/unknown side effects 2. Expensive to produce and buy

Answer 13

Any organism that damages or destroys crops/vegetables, leading to a decrease in the yield of crops.

Answer 14

Pesticides (such as insecticides) are used to kill insects that damage crops.

Answer 15

1. Pests/insects might develop resistance to the pesticide 2. Excess pesticides in soil would cause pollution in the environment 3. Effects on food chains - if pests are killed, then their predators will not have food so they will also die 4. Other insects could die just by sitting on the crops, killing useful insects such as butterflies and bees

Answer 16

Crops that release a toxin in their cells called B.t. toxin, which is lethal when the insect eats the crop. This means only pests will be killed, instead of all insects. However, not all pests can die from this toxin, so many farmers may need to spray with insecticides to kill other pests.

Answer 17

Comes from the bacterium Bacillus thuringiensis, where the gene that produces the particular toxin is taken and inserted into the DNA of GM crops. This allows crops to produce the toxin.

Answer 18

Using organisms to control pests or weeds by killing them.

Answer 19

Mineral ions such as nitrates, potassium and phosphates.

Answer 20

Nitrates are needed for making DNA, protein synthesis hence needed for plant growth.

Answer 21

Advantages: 1. Increases crop yield Disadvantages: 1. May cause pollution of surrounding water if too much is added, by leaking into lakes and rives when it rains 2. Harming other organisms and potentially killing them 3. Health problems for humans and animals drinking the polluted water

Answer 22

Advantages: 1. No use of chemicals 2. Increase crop yield 3. No pollution Disadvantages: 1. The predators may cause other damage, such as eating helpful insects that eat other pests 2. Eating the crop

Answer 23

1. Control organism stays mainly within the crop 2. Control organism selectively chooses to eat pests of the crop 3. Control organism does not eat beneficial organisms or crop plants