Exam-style practice (harder): Biology multiple choice quiz

Q secretes little or no insulin, which is consistent with type 1 diabetes.

Q's target cells respond poorly to insulin, consistent with type 2 diabetes.

Q releases glucagon as glucose rises, which keeps Q's blood glucose high.

P is hypoglycaemic, because P's blood glucose falls back to 5.0 mmol/L.

0

$\frac{1}{2}$

$\frac{1}{8}$

$\frac{1}{4}$

Re-isolate the bacterium from the new spots and show it matches the original culture.

Show that an antibiotic applied to infected plants stops the leaf spot from spreading.

Inoculate a second group of healthy plants with sterile nutrient broth as a control.

Show that the bacterium can also be isolated from a sample of healthy bean leaves.

Trp is replaced by Cys, so one amino acid in the chain changes.

Every amino acid after Ala changes, because the reading frame shifts.

The chain stops after Ala, so a shortened polypeptide is produced.

There is no change, because third-base changes are always silent.

Cases rose far faster than coverage fell, consistent with a loss of herd immunity.

The vaccine became less effective each year, so more vaccinated people got measles.

Cases rose in proportion to the fall in coverage, by about 9% over the five years.

The data prove that falling coverage alone caused the rise in measles cases.

A diverging lens, because light from near objects focuses behind the retina.

A converging lens, because light from near objects focuses in front of the retina.

A diverging lens, because the lens of the eye is too strongly curved.

A converging lens, because light from near objects focuses behind the retina.

Repeat each temperature five times instead of three and average the results.

Keep each tube in a thermostatic water bath for the full 10 minutes.

Measure CO₂ with a gas syringe reading to 0.1 mL instead of 1 mL.

Add two more temperatures, 65 °C and 75 °C, to extend the range tested.

The antibiotic caused new resistance mutations, raising resistance to 25%.

From day 2 to day 6, resistant cells reproduced faster than susceptible cells.

About 2 million resistant cells were present before and after treatment.

By day 6, most of the population was resistant to the antibiotic.

Long-lasting protection, because injected antibodies become memory B cells.

Protection from 1 to 2 weeks later, once a primary immune response is mounted.

Immediate protection against most bacterial toxins, as antibodies are non-specific.

Immediate but short-lived protection, as no memory cells are produced.

Less ADH was released after the water drink, so less water was reabsorbed.

More ADH was released after the water drink, so collecting ducts leaked less.

The salt drink increased blood volume, so the kidneys made more dilute urine.

Aldosterone rose after the water drink, so more sodium and water were lost.

4 times

6 times

2.5 times

1.5 times

6 pg after meiosis I and 3 pg after meiosis II

24 pg after meiosis I and 12 pg after meiosis II

12 pg after meiosis I and 6 pg after meiosis II

12 pg after meiosis I and 12 pg after meiosis II

Man 1, as he has both bands the child could not have got from the mother.

Man 3, as he shares more bands with the child than either other man does.

Man 2, as he shares both the 3.4 kb and 5.0 kb bands with the child.

None can be ruled out, as each man shares at least two bands with the child.

Broth in a flask sealed airtight after boiling stays clear for weeks.

A swan-neck flask stays clear, but clouds once its neck is snapped off.

Broth in an open beaker turns cloudy within a few days of boiling.

Boiled broth in an open beaker stays clear longer than unboiled broth.