Grade 12 Biology diagnostic

15 questions on cells & microscopy, human biology & physiology, genetics & inheritance, ecology & populations and measurement & evidence, plus 3 from Grade 11. Answer what you can, then check your answers to see which topics are secure and what to practise next.

15 questions5 topicsAbout 15 minutesSet 5 of 5

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

1Cells & microscopyWhich structure is found in plant cells but not in animal cells: the nucleus or the chloroplast?

A. the chloroplastB. the nucleus

2Cells & microscopyDoes every mature cell divide at the same rate?

A. Only if cells are the same color.B. Yes, all once per hour.C. No.

3Human biology & physiologyA fictional circulation model has 58 beats/min and 72 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

4Human biology & physiologyA supplied signal travels 12 distance units in 3 time units. Find its average model speed.

Your answer

5Genetics & inheritanceUsing base-pairing rules, which sequence pairs with the DNA strand CTGAGGAG, read base by base in the same order?

A. GACTCCTCB. CTGAGGAGC. GACUCCUCD. CACTCCTC

6Genetics & inheritanceIn the simple Aa × Aa inheritance model with independent outcomes, the probability of aa is 1/4. Among 276 offspring, find the expected aa count, not a guaranteed outcome. Round to 3 decimal places if needed.

Your answer

7Genetics & inheritanceIn a canonical double-stranded DNA sample, adenine is 25% of all bases. Find the guanine percentage, assuming A = T and C = G. Round to 3 decimal places if needed. Answer in %.

Your answer%

8Ecology & populationsSupplied fictional records give M = 53 initially marked, C = 59 in a later sample, and R = 39 marked in that sample. Use N ≈ MC/R under the stated assumptions. No animals are to be handled. Round to 3 decimal places if needed.

Your answer

9Ecology & populationsA fictional population starts at 158. During one interval: 15 births, 21 arrivals, 15 deaths and 10 departures. Find the final count. Round to 3 decimal places if needed.

Your answer

10Ecology & populationsIn this simplified food chain: oak trees → caterpillar → songbird → hawk. At which trophic level is “caterpillar”? (Producers are level 1.)

Your answer

11Measurement & evidenceWhich conclusion matches a small controlled study more closely?

A. The result proves every possible mechanism.B. Under these tested conditions, the measured groups differed.C. Every organism everywhere will always respond the same way.

12Measurement & evidenceInvestigation: Yeast is mixed with sugar water at 20 °C, 30 °C and 40 °C, using the same mass of sugar each time, and the gas bubbles released per minute are counted. In this investigation, which is the dependent variable?

A. the number of gas bubbles per minuteB. the mass of sugarC. the temperature

From Grade 11

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

13Evolution & biodiversity (Grade 11)Does being drawn farther right on a tree mean a species is more evolved?

A. Yes, always.B. No.C. Only if the line is thicker.

14Genetics & inheritance (Grade 11)The same sample has 20% A and 20% T. What percentage is G if the remainder is equally C and G?

Your answer%

15Human biology & physiology (Grade 11)Which vessels are associated with exchange with tissues?

A. Only solid bone canals.B. Capillaries.C. Only the largest arteries.