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

5

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

4

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

7

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

The actual length of a cell structure is 8 µm. Which steps are used to calculate the magnification of an electron micrograph of this cell structure?...

2019 Summer

5

MCQ

CH1 - CELL STRUCTURE

What is the typical resolution of a microscope using daylight as a light source with a ×10 eyepiece lens and a ×40 objective lens?

2019 Summer

4

MCQ

CH1 - CELL STRUCTURE

Two different types of cell, P and Q, were broken up using ultrasound and their contents analysed. Both types of cell contained small circular DNA. Th...

2019 Summer

6

MCQ

CH1 - CELL STRUCTURE

Which features shown in the diagram can be present in viruses?

2019 Summer

3

MCQ

CH2 - BIOLOGICAL MOLECULES

After boiling a sample of milk with Benedict’s solution, a yellow colour is observed. Which conclusion about the sample of milk is correct?

2019 Summer

3

MCQ

CH2 - BIOLOGICAL MOLECULES

Which of the statements about polysaccharides can be used to describe amylose and cellulose?1. contains 1,4 glycosidic bonds2. contains 1,6 glycosidic...

2019 Summer

3

MCQ

CH2 - BIOLOGICAL MOLECULES

Which diagram shows the formation of a peptide bond?

2019 Summer

3

MCQ

CH3 - ENZYMES

In enzyme-catalysed reactions, the position of the amino acids found at the active site is important. During the synthesis of enzymes, amino acids are...

2019 Summer

3

MCQ

CH2 - BIOLOGICAL MOLECULES

Which features affect the tensile strength of collagen?1 the helical structure of collagen chains2 the small R group of the amino acids in collagen3 t...

2019 Summer

3

MCQ

CH3 - ENZYMES

A fixed volume of the enzyme catalase was added to a fixed volume of hydrogen peroxide solution. The diagram shows how the concentration of product ch...

2019 Summer

3