Theory

CH14 - HOMEOSTASIS

(a) In mammals, blood glucose concentration is maintained around a set point so that the mammal can function efficiently. This is an example of homeos...

2024 Summer

7

Theory

CH14 - HOMEOSTASIS

(a) Blood glucose concentration is maintained around a set point by homeostasis. Explain the principles of homeostasis.[4]  (b) Glycogen phospho...

2024 Winter

5

Theory

CH14 - HOMEOSTASIS

(a) Fig. 1.1 is a diagram of part of a Bowman's capsule and a glomerular capillary. (i) Identify structures A and B. (ii) The glomerular filtrate ...

2024 Winter

5

Theory

CH14 - HOMEOSTASIS

(a) Fig. 1.1 is a diagram of a nephron. Label Fig. 1.1 using: • one labelling line and the letter A to identify a region that contains urine ...

2024 Spring

4

Theory

CH14 - HOMEOSTASIS

Osmoregulation is the control of the water potential of body fluids such as blood. (a) Osmoreceptors and antidiuretic hormone (ADH) have an important...

2024 Summer

4

Theory

CH14 - HOMEOSTASIS

The mammalian kidney is responsible for: • the excretion of urea • osmoregulation (the homeostatic control of the water potential of the b...

2024 Winter

9

Theory

CH14 - HOMEOSTASIS

The kidney is an important organ of homeostasis. One role of the kidney is osmoregulation.  (a) Fig. 5.1 is a photomicrograph of part of a kidne...

2023 Summer

8

Theory

CH14 - HOMEOSTASIS

(a) Fig. 1.1 is a drawing of a longitudinal section (LS) of a human kidney. Use the letters A, B, C and D in Fig. 1.1 to complete Table 1.1. Each ...

2023 Spring

3

Theory

CH14 - HOMEOSTASIS

Amino acids are the monomers that are used to produce proteins in organisms. Amino acids also have other, non-protein, roles in the body. (a) Fig. 7....

2023 Summer

5

Theory

CH14 - HOMEOSTASIS

(a) (i) When blood glucose concentration decreases, glucagon is released by the pancreas into the blood and is transported to the cells.  Fig. 6...

2023 Winter

2

MCQ

CH1 - CELL STRUCTURE

Which statements about resolution and magnification are correct?[Table_1]

2018 Summer

3

MCQ

CH1 - CELL STRUCTURE

An eyepiece graticule has a scale with 100 divisions. A stage micrometer has a scale with 50 divisions, each of which is 0.040 mm apart. Using a ×40 ...

2018 Summer

9

MCQ

CH1 - CELL STRUCTURE

A prokaryotic cell which is 1 µm in diameter, is magnified 50000 times in an electron micrograph. What is the diameter of the cell in the electron m...

2018 Summer

8

MCQ

CH1 - CELL STRUCTURE

A scientist carried out an experiment to separate cell structures in animal cells. The cells were broken open to release the cell structures. This ext...

2018 Summer

5

MCQ

CH1 - CELL STRUCTURE

Radioactively-labelled nucleotides are introduced into a cell.In which cell structures will the radioactivity first become concentrated?

2018 Summer

4

MCQ

CH2 - BIOLOGICAL MOLECULES

What is the general formula for amylose?

2018 Summer

3

MCQ

CH2 - BIOLOGICAL MOLECULES

The diagram shows relationships between some important molecules and bonds. What is represented by circles numbered 1, 2 and 3?

2018 Summer

4

MCQ

CH2 - BIOLOGICAL MOLECULES

In unsaturated lipid molecules, where are double bonds located?

2018 Summer

3

MCQ

CH2 - BIOLOGICAL MOLECULES

Phospholipids and triglycerides are important biological molecules.Which properties are correct for these molecules?[Table_1]

2018 Summer

3

MCQ

CH2 - BIOLOGICAL MOLECULES

The diagrams show two arrangements of amino acids in a protein. Which row correctly names the bonds at S or T?

2018 Summer

4