gr 10-bio (unit 1.3)

Question 1

geographical barrier

Answer 1

• an environmental barrier

- eg. large canyon, river, etc…

Question 2

artificial selection

Answer 2

-selective pressure exerted by humans to improve or modify particular desirable traits

Question 3

monoculture and the risks/ consequences of it

Answer 3

• a large amount of the same crop in the same area
• if they are the same there is no genetic diversity
• so if disease or environmental changes arise it will wipe them out

Question 4

what are the consequences of using artificial selection?

Answer 4

• can result in hurting the organism
• eg. English bulldogs are selectively bred for their flat faces; this causes respiratory problems
• eg. german shepherds large size; causes hip and joint disorders

Question 5

what environmental agents can result in mutations/ the three mutagens?

Answer 5

• x-rays, UV radiation- physical mutagen
• chemical mutagen- molecules that enter the nucleas of the cell snd chemically react with DNA (eg. nitrite, gasoline fumes)
• carcinogen- substance or agent that causes cancer (exposure to the sun)

Question 6

What’s the difference between occurring mutations in somatic cells and gamete cells?

Answer 6

somatic cells: the mutation occurs but when the organism dies the mutation disappears from the population/furthering on
gamete cells: if a mutation occurs in the egg or sperm cells the mutation may get passed on

Question 7

speciation (adaptive radiation)

Answer 7

-organisms that diversify rapidly due to selective pressure

Question 8

what is a selective advantage?

Answer 8

-a mutation or genetic advantage that helps an organism survive better than its competitors

Question 9

speciation

Answer 9

-formation of new species

Question 10

what is staphylococcus aures?

Answer 10

• bacteria that causes infections
• each individual bacterium produces asexually, and very quickly
• each has an advantage mutation to help survive environments
• the surviving/remaining bacteria that wasn’t killed by a certain bacteria rapidly reproduces which leads to more medications

Question 11

what are mutations?

Answer 11

• changes in DNA

- provide new alleles and are a source of new genetic variation when inherited

Question 12

how does extinction occur?

Answer 12

-by selective pressure

Question 13

adaptation

Answer 13

-a structural, behavioural, or physiological process that helps an organism survive

Question 14

how can mutations occur? what are some reasons to increase the chances?

Answer 14

• can occur out of nowhere/ spontasualy when DNA is being copied before a cell divides
• may also occur from environmental agents like Uv radiation etc…

Question 15

what is an example of a mutation that is harmful or not beneficial?

Answer 15

• a cell that dies, malfunctions, or multiply more than it should is harmful
• some mutations are neither harmful nor beneficial

Question 16

what is natural selection?

Answer 16

• natural selections is the process that results when the characteristics of a population, change over many generations due to environmental changes
• happens because organisms with certain traits are more successful in specific local environmental conditions
• for this to occur there needs to be genetic diversity within a species or population