Chapter 7: Biotechnology in Agriculture & Environmental Conservation

Question 1

how can recombinant DNA technology be used in agriculture

Answer 1

herbicide-resistant crops
disease-resistant crops
faster growth rate
greater product quality and yield
tolerance to adverse environmental conditions

Question 2

what should conservation planning consider

Answer 2

biogeography
reproductive behaviour
population dynamics

Question 3

what can biotechnology be used for in environmental conservation

Answer 3

monitoring endangered species
assessing gene pools for breeding programs
quarantine

Question 4

what are the ethical issues concerned with transgenic organisms

Answer 4

effects on non-target organisms
more rapid evolution of pesticide-resistance crops
emergence of super-weeds
reduction in genetic diversity in GMO crop plants

Question 5

Explain how a consideration of population dynamics can assist conservation planning to
maintain viable gene pools in a vulnerable species, such as the malleefowl.

Answer 5

can identify trends in population size or when populations will grow/decline
smallest population sizes pose the most risk to gene pool or population
will lose genetic diversity when small
(therefore) conservation planning should be based around smallest
population size or should allow for times when population numbers will
drop or should consider small sizes in the past
can identify and potentially correct factors that cause numbers to drop

Question 6

Explain a possible adverse environmental effect that could result from farming
herbicide-resistant canola.

Answer 6

Will not be able to use herbicides to kill the canola plant.
These plants could spread and become a nuisance.
Potential for the herbicide resistance gene to spread to other
species.
This could create a super weed/a nuisance plant that is resistant to
herbicide
Relatively new/Untried
Consequences are not fully understood
Over use of herbicide/increased use
Leading to evolution of herbicide-resistant weeds/death of
non-target species

Question 7

Explain an advantage of using DNA recombinant technology, rather than artificial
selection, to produce a herbicide-resistant strain of canola.

Answer 7

Can take a gene from a completely unrelated organism
Greater chance of finding a gene with (broad/strong/desirable)
herbicide resistance
Relatively quick
Can produce a strain within one or few generations or artificial
selection can take many generations to fix herbicide resistance in a
trait
Only manipulate herbicide resistance
Allows retention of other desirable characteristics in the strain or
artificial selection for one trait can inadvertently lead to changes in
other traits

Question 8

Explain how the use of transgenic crop plants may have adverse biological effects. (10 marks)

Answer 8

As transgenic crops contain traits advantageous to survival. in their environment, they. may show.
increased growth and become difficult to control. This increases the risk of transgenic plants.
outcompeting other non-modified plant species and changing the ecosystem’s food web.
Transgenic crops may also exchange transgenes with other plant species. The transgene may
provide the plants with resistance to factors limiting their growth such as pests or herbicides. This
could lead to the species becoming a weed or pest as they are no longer able to be controlled by ….
previous limiting factors.

Question 9

Reasons for making transgenic organisms

Answer 9

1. To increase crop and livestock resistance
   * Increased protection against pests, diseases, and extreme environmental conditions
2. To study human diseases
   * Can be used to predict how certain drugs and treatments affect humans with certain conditions
3. To increase the productivity, yield and quality of crops and livestock
4. To create new products. E.g., Blue roses, Roses modified with pansy genes
5. To produce therapeutic products
   * Used to produce proteins including hormones, cytokines, enzymes, vaccines and antibodies which have applications in research and medicine

Question 10

Outline the role that Agrobacterium plays in the production of transgenic plants and explain why it is well.
suited to this role.

Answer 10

Agrobacterium can be used as a vector to transfer foreign genes into plants. By removing its
crown gall tumour-inducing gene and inserting a target gene, the bacterium inserts the target
gene into the plant’s DNA, creating a transgenic organism. Agrobacterium. is well suited to this
role as it. can naturally transfer its DNA into host plants while infecting them, and so requires
little modification. its ability to infect a broad range of host plants makes it a versatile way to
make transgenic organisms:

Question 11

Benefits of transgenic organisms to society.

Answer 11

I. Pest resistance
Agricultural scientists use recombinant DNA technology to create crops, such as Bt cotton, with
pesticide, herbicide or disease resistance. This promotes higher crop yield and is less expensive and
time consuming than combining genes through artificial selection.

2. Medical treatment
   Recombinant DNA technology is also used for medical treatment such as the production of human
   insulin to treat diabetes. This allows large amounts of human insulin to be produced quickly, and
   replaces the need for animal insulin which can cause adverse reactions.