Grade 9 Biology diagnostic

16 questions on plant biology, cells & microscopy, human biology & physiology, genetics & inheritance, evolution & biodiversity, ecology & populations and measurement & evidence, plus 2 from Grade 8. Answer what you can, then check your answers to see which topics are secure and what to practise next.

16 questions7 topicsAbout 20 minutesSet 4 of 5

Skip a question if you do not know the answer. It is better than guessing, because it shows what to practise.

1Plant biologyIn supplied data, 11 of 38 seeds germinated under the stated test conditions. Find the sample germination percentage. Round to 3 decimal places if needed. Answer in %.

Your answer%

2Plant biologyWhich conclusion is justified by 30 of 40 tested seeds germinating?

A. Exactly 75% of all future seeds everywhere will germinate.B. 75% germinated in this tested sample and conditions.C. The other seeds are certainly all dead.

3Cells & microscopyWhat is a selectively permeable membrane?

A. A barrier that always blocks everything.B. A wall that ignores molecule properties.C. A barrier that permits some substances more readily than others.

4Cells & microscopyA printed image is 21 mm long at 200× magnification. Find the actual length in micrometers. Round to 3 decimal places if needed. Answer in µm.

Your answerµm

5Human biology & physiologyA fictional circulation model has 68 beats/min and 68 mL/beat. Find its flow in mL/min. These are supplied model values, not diagnostic ranges. Round to 3 decimal places if needed. Answer in mL/min.

Your answermL/min

6Human biology & physiologyWhat defines an artery?

A. It always contains oxygen-rich blood without exceptions.B. It carries blood away from the heart.C. It has no wall.

7Genetics & inheritanceA DNA template strand reads TATAGCAC. Which mRNA sequence is transcribed from it, read base by base in the same order?

A. TATAGCACB. CUAUCGUGC. AUAUCGUGD. ATATCGTG

8Genetics & inheritanceA fictional diploid organism has 18 chromosomes in a normal somatic nucleus. In the standard meiosis model, how many chromosomes are in a haploid gamete? Round to 3 decimal places if needed.

Your answer

9Evolution & biodiversityWhich data can contribute to classification?

A. Only market price.B. Molecular sequences and anatomical traits.C. Only a favorite common name.

10Evolution & biodiversityWhat are homologous structures?

A. Structures found only in fossilsB. Structures in different species that share an underlying pattern because of common ancestry, such as the bones of a human arm and a bat wingC. Structures that no longer have any functionD. Structures that look the same but evolved separately

11Ecology & populationsA fictional population starts at 758. During one interval: 67 births, 17 arrivals, 7 deaths and 6 departures. Find the final count. Round to 3 decimal places if needed.

Your answer

12Ecology & populationsA supplied survey counts 170 plants in 3 non-overlapping quadrats, each 1 m². Find the mean density in the sampled area. Round to 3 decimal places if needed. Answer in plants/m².

Your answerplants/m²

13Measurement & evidenceIndependent measured heights are 8, 10 and 12 cm. Find the mean.

Your answercm

14Measurement & evidenceInvestigation: Pondweed is placed at different distances from a lamp in the same volume of water, and the oxygen bubbles it gives off per minute are counted. In this investigation, which is a controlled variable?

A. the distance from the lampB. the number of oxygen bubbles per minuteC. the volume of water

From Grade 8

These questions check skills from the grade below, so gaps can be spotted early.

15Ecology & populations (Grade 8)Using the stated convention, grass → rabbit means what?

A. The rabbit obtains energy by eating grass.B. Grass eats the rabbit.C. The arrow means both are identical.

16Cells & microscopy (Grade 8)Which statement is most accurate?

A. Every cell has the same shape and number of organelles.B. Different cell types can have different structures and functions.C. Cells contain no chemical reactions.