Biodiversity and why it keeps ecosystems steady
Grade 9 Science Worksheet - Building Confidence

Circle the best answer.
Read this first
A field note about one meadow (model data)
what is counted number different plant species in the meadow 14 Pia reads a field note about one meadow. Which kind of diversity does the note count?
- Genetic diversity: the versions of genes inside one species
- Population size: the number of plants in the meadow
- Species diversity: the number of kinds of species in the meadow
- Ecosystem diversity: the number of different ecosystems in an area
A field note about one nature area (model data)
what is counted number different ecosystems in the area: a pond, a meadow and a woodland 3 Bo reads a field note about one nature area. Which kind of diversity does the note count?
- Habitat size: how much land the area covers
- Genetic diversity: the versions of genes inside one species
- Ecosystem diversity: the number of different ecosystems in an area
- Species diversity: the number of kinds of species in the area
Plants counted in two meadows (model data)
species meadow A plants meadow B plants clover 10 25 yarrow 10 25 dandelion 10 0 plantain 10 0 Jun reads the table of plants in two meadows. Which meadow has more species, and how many?
- Meadow A, with 40 plants in total
- Meadow B, with 2 different species
- Meadow A, with 4 different species
- Meadow B, with 50 plants in total
Species found in two plots (model data)
plot species found number of species X oak, maple, birch 3 Y oak, maple, birch, elm, pine 5 Kira reads the table of species found in two plots. How many more species does plot Y have than plot X?
- 8 more species: the two counts added
- 5 more species: the species in plot Y
- 2 more species: 5 − 3
- 3 more species: the species in plot X
Trees counted in one woodland (model data)
species trees oak 12 maple 8 birch 5 elm 5 Luz reads the table of trees counted in one woodland. How many species are in the woodland?
- 30 species: the trees added up
- 5 species: the birch count
- 4 species: oak, maple, birch and elm
- 12 species: the oak count
Milo reads the graph. What was the growth of the one-species plot in year 2, the dry year?
- 800 grams per square meter: the start of both lines
- 400 grams per square meter
- 600 grams per square meter: the many-species line
- 760 grams per square meter: the one-species line in year 3
Noah reads the graph. Year 2 was a dry year. Which statement about year 2 is correct?
Plant growth in two plots over four years (model data). Year 2 was a dry year. Time (years) across, 1 to 4, a mark every 1. Plant growth (grams per square meter) up, 0 to 600, a mark every 100. Many-species plot joins (1, 500), (2, 375), (3, 490), (4, 500). One-species plot joins (1, 500), (2, 250), (3, 470), (4, 500) with straight pieces. Plant growth in two plots over four years (model data). Year 2 was a dry year. Time (years) across, 1 to 4, a mark every 1. Plant growth (grams per square meter) up, 0 to 600, a mark every 100. Many-species plot joins (1, 500), (2, 375), (3, 490), (4, 500). One-species plot joins (1, 500), (2, 250), (3, 470), (4, 500) with straight pieces. Plant growth in two plots over four years (model data) 1 2 3 4 0 100 200 300 400 500 600 Time (years) Plant growth (grams per square meter) Many-species plot One-species plot Year 2 was a dry year. - Both plots fell, and the one-species plot fell further, to 250
- Just the one-species plot fell; the many-species plot stayed at 500
- Both plots fell, and the many-species plot fell further, to 375
- Both plots fell by the same amount, 125
Esme reads the graph. In which year were both lines lowest?
Plant growth in two plots over five years (model data). One of the five years was dry. Time (years) across, 1 to 5, a mark every 1. Plant growth (grams per square meter) up, 0 to 700, a mark every 100. Many-species plot joins (1, 600), (2, 600), (3, 450), (4, 590), (5, 600). One-species plot joins (1, 600), (2, 600), (3, 300), (4, 570), (5, 600) with straight pieces. Plant growth in two plots over five years (model data). One of the five years was dry. Time (years) across, 1 to 5, a mark every 1. Plant growth (grams per square meter) up, 0 to 700, a mark every 100. Many-species plot joins (1, 600), (2, 600), (3, 450), (4, 590), (5, 600). One-species plot joins (1, 600), (2, 600), (3, 300), (4, 570), (5, 600) with straight pieces. Plant growth in two plots over five years (model data) 1 2 3 4 5 0 100 200 300 400 500 600 700 Time (years) Plant growth (grams per square meter) Many-species plot One-species plot One of the five years was dry. - Year 5, the last point on the graph
- Year 4, when both lines rose again
- Year 3, when both lines dipped
- Year 1, the first point on the graph
Growth in one many-species plot (model data)
time growth (grams per square meter) before the dry year 400 during the dry year 300 Ren reads the table for a plot with many species. How much growth did the plot lose during the dry year?
- 700 grams per square meter: 400 + 300
- 0 grams per square meter: a plot with many species does not change
- 100 grams per square meter: 400 − 300
- 300 grams per square meter: the growth in the dry year
Growth in three plots (model data)
plot species before the dry year during the dry year A 1 500 250 B 4 500 350 C 16 500 400 Zee reads the table. Which plot lost the least growth during the dry year?
- Plot A, which lost 250 grams per square meter
- Plot C, which lost 0 because it has the most species
- Plot B, which lost 150 grams per square meter
- Plot C, which lost 100 grams per square meter