ConceptConceptDocsDocuments

Edexcel IAL Biology Topic 1 Molecules, Transport and Health

Identify the molecule, vessel or physiological process first, then use labelled structures, mark-scheme terminology and quantitative evidence to build the explanation.

Syllabus
First assessment 2019
Course
Biology YBI11
Level
AS

Exam points

  • Describe biological molecules through monomers, bonds, functional groups and structure.
  • Interpret vessel, heart and dissociation evidence to explain transport and exchange.
  • Apply practical methods, calculations and health data with correct variables and units.

Covered syllabus points

1.1—Water as a transport solvent1.2—Monosaccharides, disaccharides and polysaccharides1.3—Core Practical 1 - reducing sugars and starch1.4—Glycosidic bonds, condensation and hydrolysis1.5—Triglycerides and saturated or unsaturated lipids1.6—Need for hearts and circulation1.7—Blood vessel structure and function1.8—Cardiac cycle and mammalian heart function1.9—Haemoglobin, oxygen dissociation and Bohr effect1.10—Atherosclerosis1.11—Blood clotting and cardiovascular disease1.12—Cardiovascular disease risk factors1.13—Antioxidants and cardiovascular disease risk1.14—Core Practical 2 - vitamin C content1.15—Health risk data, correlation and causation1.16—Study design for health risk factors1.17—Perceived risk and actual risk1.18—Cholesterol, HDL, LDL and CVD evidence1.19—Scientific knowledge and CHD risk reduction1.20—Treatments for cardiovascular disease

Topic 1 - Molecules, Transport and Health question 1

[Maximum number: 2]

The structure and properties of the cell membrane are important in controlling which molecules can enter and leave a cell.

The diagram shows the permeability of cell membranes to some chemicals.
sodium and chloride ions

Figure for Question Topic 1 - Molecules, Transport and Health question 1 — Edexcel A-Level Biology AS

The sodium and chloride ions, glucose and water are polar chemicals.
A steroid is a non-polar chemical.

Describe the dipolar nature of water.

Topic 1 - Molecules, Transport and Health question 2

[Maximum number: 11]

The structures of polysaccharides, disaccharides and monosaccharides relate to their roles in living organisms. They are all types of carbohydrate.

Question (a)

(a)

The table shows the main type of carbohydrate present in some foods.

Table for Question (a) — Edexcel A-Level Biology AS
[ 5 ]

Question (i)

(i)

Which row of the table shows an example of a polysaccharide, a disaccharide and a monosaccharide? □ A □ B □ C □ D

Table for Question (i) — Edexcel A-Level Biology AS
[ 1 ]

Question (ii)

(ii)

Lactose is a disaccharide composed of galactose and glucose. Complete the diagram to show a molecule of lactose.

Figure for Question (ii) — Edexcel A-Level Biology AS
Figure for Question (ii) — Edexcel A-Level Biology AS
[ 2 ]

Question (iii)

(iii)

Glycogen is another carbohydrate.

Describe the structure of glycogen.

[ 2 ]

Question (b)

(b)

*(c) Carbohydrate metabolism includes the group of chemical reactions that break down carbohydrates. Some of these reactions convert one type of carbohydrate into another type. The flowchart shows what happens to some of the carbohydrates that we eat.

Figure for Question (b) — Edexcel A-Level Biology AS

Explain how carbohydrates are metabolised, transported and used in the cells of the body and stored in liver cells. Use the information in the question and your own knowledge of the structures, roles and properties of carbohydrates and transport mechanisms.

[ 6 ]

Topic 1 - Molecules, Transport and Health question 3

[Maximum number: 4]

A simple test can be used to assess the quantity of sugar in liquids, such as food extracts and urine.

Question (a)

(a)

Describe how a urine sample can be tested for glucose.

[ 2 ]

Question (b)

(b)

Complete the table of results from tests on standard glucose solutions.

Table for Question (b) — Edexcel A-Level Biology AS
[ 2 ]
All question bank results loaded