| Date | November 2017 | Marks available | 8 | Reference code | 17N.2.HL.TZ0.07 |
| Level | Higher level | Paper | Paper 2 | Time zone | TZ0 / no time zone |
| Command term | Explain | Question number | 07 | Adapted from | N/A |
Question
Nitrogen is part of many important substances in living organisms.
Draw labelled diagrams to show a condensation reaction between two amino acids.
Nitrogen is part of many important substances in living organisms.
Distinguish between transcription and translation.
Nitrogen is part of many important substances in living organisms.
Explain how insects excrete nitrogenous wastes.
Markscheme
a. at least one of the amino acid structures completely correct
b. peptide bond shown with N–C and C=O and N–H correct
c. release of water clearly shown
a. DNA is transcribed AND mRNA is translated
Disallow the first mark, if a candidate gets transcription and translation the wrong way round, but allow marks
after that up to [3 max]
b. transcription produces RNA AND translation produces polypeptide/protein
c. RNA polymerase used in only in transcription and ribosomes only in translation
d. transcription in the nucleus «of eukaryotes» and translation in the cytoplasm
e. tRNA needed for translation but not transcription
f. nucleotides linked in transcription and amino acids in translation
OR
sugar-phosphate/phosphodiester bonds in transcription and peptide bonds in translation
[Max 4 Marks]
a. excreted as uric acid
b. excretion by Malpighian tubules
c. nitrogenous waste/ammonia «accumulates» in hemolymph
d. nitrogenous waste/ammonia absorbed by Malpighian tubules
e. ammonia converted to uric acid
f. conversion to uric acid requires energy/ATP
g. high solute concentration in Malpighian tubules
OR
active transport of ions/Na+/K+ into Malpighian tubules
h. water absorbed by osmosis flushes uric acid/nitrogenous waste to «hind» gut
i. water/ions reabsorbed from the feces and returned to hemolymph
j. uric acid precipitates/becomes solid/forms a paste so can pass out with little water
k. uric acid excreted/egested with the feces
l. water conservation/osmoregulation
OR
reduces mass of water «in body»
m. uric acid is non-toxic
[Max 8 Marks]
Examiners report
Syllabus sections
- 18M.1.HL.TZ1.39: The presence of proteins such as albumin in a urine sample indicates kidney damage. Where in...
- 17M.1.HL.TZ1.39: The table shows solute concentrations in normal blood plasma and the fluid in one section of...
- 22M.1.HL.TZ1.39: Glucose moves from the filtrate in the nephron into the bloodstream during normal kidney...
-
22M.1.HL.TZ2.39:
The micrograph shows a glomerulus and Bowman’s capsule, where ultrafiltration takes place in the kidney.
[Source: MICROSCAPE/SCIENCE PHOTO LIBRARY.]
What facilitates the formation of glomerular filtrate?
A. Many fenestrations in walls of capillaries in the glomerulus
B. High pressure in the Bowman’s capsule
C. ADH secreted by the pituitary gland
D. Osmosis caused by a high concentration of urea in the blood
- 17M.2.HL.TZ1.1f.i: Identify which of these turtle groups represent the control, giving a reason for your answer.
- 17M.2.HL.TZ1.1b: Compare and contrast the changes in urea excretion in the mouth with the changes in urea...
-
16N.1.HL.TZ0.39:
Which kidney adaptation would be expected in the desert kangaroo rat (Dipodomys deserti)?
A. Increased nephron density
B. Longer proximal convoluted tubule
C. Longer loop of Henle
D. Increased ADH receptors on the collecting duct
-
18N.2.HL.TZ0.5a:
Label region X and structure Y on the diagram of the kidney.
[Source: PeterHermesFurian/iStock]
- 18N.2.HL.TZ0.5b: Distinguish between osmoregulators and osmoconformers.
- 21M.1.HL.TZ1.38: What is normally found in the urine of a healthy individual? A. Glucose B. Red blood...
- 17M.1.SL.TZ1.1: Which structure found in eukaryotes has a single membrane? A. Nucleus B. Lysosome C....
- 17M.2.HL.TZ1.1c.i: Describe the trends shown by the graph for dissolved oxygen in water discharged from the mouth.
- 17M.2.HL.TZ1.1d: Deduce with a reason whether a urea transporter is present in the mouth of P. sinensis.
- 18M.1.HL.TZ2.39: What is the effect of ADH on the kidney? A. It stimulates ultrafiltration in the Bowman’s...
- 21M.1.HL.TZ2.39: What sequence shows the route taken by nitrogenous wastes in insects from their production in...
- 17M.1.HL.TZ2.38: The graph shows the daily amount of the residue of a drug in the wastewater of a...
-
22M.2.HL.TZ1.6c:
Explain how water balance is restored in mammals when they are dehydrated.
-
22M.2.HL.TZ2.8b:
Humans need to balance water and solute concentrations and also excrete nitrogenous wastes. Explain how the different parts of the kidney carry out these processes.
-
22M.2.HL.TZ2.8c:
Describe adaptations in mammals living in desert ecosystems to maintain osmolarity in their bodies.
-
17N.2.HL.TZ0.03c:
Describe the role of ADH in human osmoregulation.
-
20N.2.HL.TZ0.7c:
Explain the role of the kidney in osmoregulation.
- 17M.2.HL.TZ1.1a: Deduce whether the excretion of ammonia or urea changes more when a turtle emerges from water.
-
17M.2.HL.TZ1.1g:
The salt marshes where these turtles live periodically dry up to small pools. Discuss the problems that this will cause for nitrogen excretion in the turtles and how their behaviour might overcome the problems.
-
21N.1.HL.TZ1.39:
Where in the nephron is most glucose reabsorbed?
[Source: National Institute of Diabetes and Digestive and Kidney Diseases, n.d. [Nephron]. [diagram online] Available at:
https://www.niddk.nih.gov/news/media-library/9164 [Accessed 23 March 2020].] - 19M.1.HL.TZ2.33: What is the function of the loop of Henle? A. To reabsorb salt B. To maintain a hypertonic...
- 19M.1.HL.TZ2.34: What is the nitrogenous waste excreted in insects? A. Urea B. Uric acid C. Ammonia D. Urine
- 17M.2.HL.TZ1.1f.ii: Suggest a reason for the greater expression of the gene for the urea transporter after an...
- 17M.2.HL.TZ1.1c.ii: Suggest reasons for these trends in dissolved oxygen.
- 18N.1.HL.TZ0.38: Which hormone influences movement of water into blood? A. Oxytocin B. Leptin C. ...
-
19M.1.HL.TZ1.39:
The image shows a transverse section through a collecting duct in a vertebrate kidney.
[Source: Professor Peter Takizawa, Yale University]
How is the movement of materials across the wall of the collecting duct affected by the release of ADH from the pituitary gland?
A. There is increased movement of water in the direction of arrow I.
B. There is increased movement of sodium in the direction of arrow I.
C. There is increased movement of water in the direction of arrow II.
D. There is increased movement of sodium in the direction of arrow II.
- 19M.2.HL.TZ1.6c: Explain how blood solute concentrations are kept within narrow limits in the human body.
- 16N.2.HL.TZ0.6c: Distinguish between the composition of the blood of the renal artery and the blood of the...
- 19N.2.HL.TZ0.7a: Outline the reasons for the differences in blood concentrations between the renal artery and...
- 19N.1.HL.TZ0.39: Damselflies are flying insects. They lay eggs that hatch into larval forms that are aquatic....
-
19M.2.HL.TZ2.6c:
ADH (antidiuretic hormone) is a peptide hormone that is produced in the hypothalamus. Explain its action in the human body.
