Read data on a helpful trait spreading through a population
Grade 9 Science Worksheet - Challenge Me
Circle the best answer.
Noah reads the bars. Which pair of statements about generation 1 to generation 4 is correct?
- A rise of 36 percent points, which is a 36% increase on 16%
- A rise of 36 percent points, which is a 225% increase on 16%
- A rise of 225 percent points, which is a 36% increase on 16%
- A rise of 36 percent points, which is a 69% increase on 52%
Read this first
Two woodlands in two generations (model data)
woodland dark, generation 1 all moths, generation 1 dark, generation 2 all moths, generation 2 North 20 50 42 100 South 30 200 50 200 Bo compares two woodlands. Which woodland's dark share rose by more percent points, and why?
- North: its count of dark moths rose by 22, more than South's 20
- South: its share rose 10 percent points, and North's rose 2
- Neither can be named, since the two woodlands count different totals of moths
- North: it started with the larger dark share, 40% against South's 15%
Ari sees the tall share go up and down across six generations. Which explanation fits the data best?
- Chance: but the share should stay at exactly 40% in each generation
- Selection: tall plants rose 8 points in generation 2, so tall plants survive better
- Selection: the share dipped to 36%, so short plants survive better
- Chance: the share swings by a few plants and has no steady direction
A small and a large population of plants, percent purple (model data)
generation population of 20 population of 2,000 generation 1 30 30 generation 2 35 36 generation 3 25 42 generation 4 30 48 Jun reads the table. Which statement about the two populations is best supported?
- The large population shows a steady rise that selection can explain, and the small one can be chance
- Each plant in the large population turned more purple with each generation that passed
- The small population shows selection, since its share rose 5 points in generation 2
- Both populations show selection, since the purple share changed from one generation to the next
Tall plants before and after a dry year (model data)
plants before after tall 1,000 900 all plants 10,000 1,500 The count of tall plants fell after a dry year. Kira asks if tall plants lost ground. What is the best reading?
- Yes: 900 tall plants is fewer than 1,000 before, so tall plants lost ground
- Yes: tall plants are 900 of 1,500, which is 6%, down from 10%
- Yes: the table has an error, since a count and a share cannot move apart
- No: the tall share rose from 10% to 60%, since short plants fell faster
Notebook
Notes on dark moths (classmate's notebook), 4 lines. Columns: line, entry. Line 1: In generation 1, 20 of 80 moths were dark, which is 25%. Line 2: In generation 2, 45 of 90 moths were dark, which is 50%. Line 3: The share rose 25 percent points, so it rose by 25%. Line 4: Dark moths survived better on soot-darkened trunks, so their share grew.
Luz reads a classmate's notebook about dark moths. Which line has the mistake?
- Line 4: dark moths could not have survived better on soot-darkened trunks
- Line 3: 25 percent points on a start of 25% is a 100% increase, not 25%
- Line 2: 45 of 90 moths is 45%, not 50%
- Line 1: 20 of 80 moths is 20%, not 25%
Notebook
Notes on a flask and an antibiotic (classmate's notebook), 4 lines. Columns: line, entry. Line 1: Before the antibiotic, 5 in 10,000 bacteria were resistant. Line 2: After three rounds, 7,200 in 10,000 bacteria were resistant. Line 3: So the antibiotic changed the bacteria and made them resistant. Line 4: Resistant bacteria left more offspring in each round, so their share grew.
Milo reads a classmate's notebook about an antibiotic. Which line has the mistake?
- Line 2: a share of 7,200 in 10,000 is too large to be a real share
- Line 3: the resistant bacteria were already there, and the antibiotic did not make them
- Line 1: no bacteria can be resistant before an antibiotic has been used
- Line 4: resistant bacteria cannot leave more offspring than the others do
Notebook
Notes on a woodland of moths (classmate's notebook), 4 lines. Columns: line, entry. Line 1: In generation 1, 30 of 120 moths were dark, which is 25%. Line 2: In generation 2, 60 of 120 moths were dark, which is 50%. Line 3: So 30 of the light moths turned dark during their lives. Line 4: Dark moths left more young, so the share of dark moths rose.
Pia reads a classmate's notebook about moths. Which line has the mistake?
- Line 1: 30 of 120 moths is 30%, not 25%
- Line 3: moths keep their color, and the share rose because dark moths left more young
- Line 2: 60 of 120 moths is 60%, not 50%
- Line 4: dark moths cannot leave more young than light moths do
Moths in a sooty woodland: each survivor leaves 2 young like itself (model data)
moth color generation 1 survive to breed (percent) dark 30 70 light 70 30 Ren reads the table. Which claim goes with the right reason?
- Claim: the dark share rose to 50%. Reason: 21 light moths turned dark during their lives
- Claim: the dark share rose to 21%. Reason: 21 dark moths survived to breed
- Claim: the dark share rose to 50%. Reason: dark moths survived at a higher percent and left more young
- Claim: the dark share rose to 70%. Reason: 70% of the dark moths survived to breed
Tala reads the bars from round 1 to round 3. Which claim goes with the right reason?
- Claim: the share rose 16 percent points, a 400% increase. Reason: 16 ÷ 4 = 4
- Claim: the share rose 16%. Reason: 20 − 4 = 16, and percent points are percents
- Claim: the share rose 400 percent points. Reason: 16 ÷ 4 = 4, and 400 is the change
- Claim: the share rose 80%. Reason: 16 ÷ 20 = 0.8, dividing by the later share