Question
(a) Fig. 1.1 shows five species of mollusc.
Use the key to identify each species. Write the letter of each species (A to E) in the correct box beside the key.
Key
(b) State two features that are shown by all molluscs.
Answer/Explanation
Ans:
(a) E
A
B
D
C
(b) soft body ;
not segmented ;
mantle ;
visceral mass ;
(muscular) foot ; ignore feet / legs
produce slime/ have slimy body ; A mucus
radula/rasping tongue/AW ;
hydrostatic skeleton ;
Question
Figure shows seven lizards that are at risk of becoming extinct.
(a) (i) Name the vertebrate group that contains lizards.
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(ii) Use the key to identify each species. Write the letter of each species (A to G) in the
correct box beside the key. One has been done for you.
(b) The effect of humans on the environment has caused the populations of the lizard species in
Fig. 1.1 to decrease.
Explain why conserving lizards is important.
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(c) Zookeepers report that isolated female Komodo dragons, Varanus komodoensis, have
produced offspring asexually. This is very unusual in vertebrates.
(i) State two disadvantages of asexual reproduction.
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(ii) State two disadvantages of sexual reproduction.
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(d) Sexual reproduction requires meiosis to occur.
(i) Define the term meiosis.
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(ii) Explain the significance of meiosis to the survival of endangered species of lizards.
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▶️Answer/Explanation
