Inorganic ionsAQA A-Level Biology: Flashcards
What these 14 flashcards ask
- What is an inorganic ion?
- Do all ions occur at the same concentration in cells and fluids?
- What determines the pH of a solution?
- What happens to pH as hydrogen ion concentration increases?
- Why must cells keep pH within narrow limits?
- Which ion is a component of haemoglobin?
- What does the iron ion in haemoglobin do?
- Why does iron deficiency cause anaemia?
- What is co-transport?
- How is a sodium ion concentration gradient maintained in ileum epithelial cells?
- How do sodium ions enter the cell during glucose absorption?
- Why does an oral rehydration drink contain sodium ions as well as glucose?
- Which molecules contain phosphate ions as a component?
- What is released when ATP is hydrolysed?
Exam questions on Inorganic ions
- Blood plasma contains sodium ions at a concentration of about 140 mmol dm⁻³, whereas free iron ions are present at less than 0.02 mmol dm⁻³. Most of the iron in blood is found inside red blood cells, as part of haemoglobin.A person's diet is deficient in iron. Explain why this reduces the amount of oxygen their blood can carry.2 marks
- During a 400 m sprint, a runner's muscle cells respire anaerobically and produce lactic acid. The pH of the muscle cell cytoplasm falls from 7.1 to 6.6 by the end of the race.Explain why the pH of the muscle cell cytoplasm falls during the sprint.2 marks
- A grower finds that tomato plants given a nutrient solution that lacks phosphate ions grow slowly, make few new cells and have small roots. Radioactively labelled phosphate ions (³²P) are then supplied to a healthy group of plants to find out where phosphorus is used.Explain why a lack of phosphate ions reduces the growth of the plants.3 marks
Written by the Exaim team, led by Shaun Daswani (Head of Upper Secondary, Improve ME Institute; MSc Financial Mathematics, Imperial College London; BSc, UCL) and Jason Daswani (operational lead, Improve ME Institute; LSE).