Smart Edu Hub

• Q1: (a) One of the characteristics of living organisms is sensitivity. Define the term sensitivity. [2]

• Mark Scheme:

• The ability to detect or sense stimuli in the internal or external environment;
• And to make appropriate responses;

• Q2: (a) Movement is a characteristic of living organisms. Define the term movement.

• Mark Scheme:

• Whole or part of an organism changes in position or changes in place; [1]
• Ignore: locomotion
• A: from place to place one place to another

• Q1: (a) Describe the meaning of the term species. [2]

• Mark Scheme: A group of organisms that can reproduce to produce fertile offspring. [2]

Q: State a factor of production and identify an example of it from the extract. [2]

• Mark Scheme:
  • Q1: West Nile virus was first discovered in the blood of a feverish woman in Uganda’s West Nile district in 1937. This virus is an arbovirus, one of a family of more than 500 known viruses transmitted by arthropods such as mosquitoes, ticks, and fleas. West Nile virus is transmitted by mosquitoes while they are feeding on the blood of birds and mammals. It is common in Africa, the Middle East, and western Asia. The disease first appeared in America in 1999. Scientists now expect it to affect the whole of America by 2006, spread by the mosquito Culex pipiens. Birds, as well as humans, are affected by the virus.
  • With reference to the mosquito, explain the binomial system of naming organisms.
  • Mark Scheme:
  • Each organism has two names / reference to genus and species;
  • Genus = Culex;
  • Trivial/species name = pipiens;
  • Reference to the use of Latin for the name / name in italics / name underlined;
  • Max: [3]

Q: Analyse, using a production possibility curve (PPC), the opportunity cost to an economy of producing more consumer goods. [6]

• Mark Scheme:
  • Up to 4 marks for the diagram:
    • Axes correctly labelled with capital/consumer goods (1).
    • Curve drawn as a curve/line sloping downward to the axes (1).
    • Movement along the curve/along the axes (1).
    • Reduction in capital goods/increase in consumer goods shown by numbers or letters or arrows (1).
  • Up to 2 marks for coherent analysis:
    • Opportunity cost is the (next) best alternative forgone (1).
    • Resources used to produce consumer goods cannot be used to produce capital goods (1).
    • Producing more consumer goods now may mean fewer consumer goods in the future (1).
    • As there may be fewer capital goods to make them (1).

• Q1: Chromosomes are made of DNA.

• (a) Describe the structure of a DNA molecule. [4]

• Mark Scheme: any four from:

• Two strands;
• Formed into (double) helix;
• Reference to four bases (A, T, C, and G);
• Pairing of A with T / C with G;
• Cross links between bases;
• [4]
• A as an annotated drawing is acceptable;

• Q2: Define market disequilibrium. [2]
• Mark Scheme:
  • When quantity demanded does not equal quantity supplied (2).
  • When there are shortages (1) or surpluses (1) of a product.

• Q3: Identify two key resource allocation questions. [2]
• Mark Scheme:
  • What to produce / produce less of one product and more of another product / less oil and more textiles (1).
  • How to produce it / how products are made / using fewer capital goods (1).

• Q1: State three features of mammals that are not found in reptiles. [3]

• Mark Scheme:

• Pinna / external ear;
• Fur;
• Mammary glands / secretes milk;
• Sweat glands;
• Endothermic / homoeothermic / warm-blooded;
• Different types of teeth;
• Three middle ear bones;

• Q: Define ‘demand’. [2]
• Mark Scheme:
  • The willingness/desire/want (1).
  • And ability to buy a product (1).
  • In a given period (1).

• Q1: Marine iguanas are reptiles. State two features that are used to classify animals as reptiles. [2]

• Mark Scheme:

• (a)(i) Features of reptiles (any two):

• (Dry) scaly skin;
• Leathery / soft-shelled eggs;

• Q1: Name one external feature that identifies an animal as an amphibian. [1]

• Mark Scheme: Reference to moist skin. [1]

• Q1: Killer whales, Orcinus orca, are mammals. State two internal features you would expect to find in a killer whale that you would not find in a fish. [2]

• Mark Scheme: any two from:

• Double circulation;
• Four-chambered heart;
• Lungs / any named part of lungs;
• Diaphragm;
• Red blood cells without nuclei;
• AVP (Any valid point);

• Q1: (ii) State two characteristics of fungi that are used to distinguish them from plants. [2]

• Mark Scheme:

• Different composition of cell wall;
• No chlorophyll / chloroplasts / heterotrophic;
• Extracellular digestion / saprophytic / decomposer / enzymes secreted from cells to digest food;
• Hyphae / mycelium;
• No (central) vacuole;
• AVP (Any valid point), e.g., multinucleate / reproduction by budding;

• Q1: State two main features of fungal cells that are used to distinguish them from the cells of prokaryotes. [2]

• Mark Scheme: Any two from:

• Nucleus;
• Mitochondria;
• Rough Endoplasmic Reticulum (rER);
• Vacuole;
• AVP (Any Valid Point);