The diagram shows an arthropod.
Which group of arthropods does it belong to?
A) arachnids
B) crustaceans
C) insects
D) myriapods
▶️ Answer/Explanation
Ans: A
The arthropod in the diagram has two body segments (cephalothorax and abdomen) and four pairs of legs, which are key features of arachnids (A).
Crustaceans (B) typically have more legs and segmented bodies, insects (C) have three pairs of legs, and myriapods (D) have many legs and elongated bodies. Since the diagram matches arachnid characteristics, the correct answer is A (Arachnids).
The drawing shows a ground squirrel. Which feature identifies this animal as a mammal?
A) eye
B) four limbs
C) fur
D) tail
▶️ Answer/Explanation
Ans: C
The defining characteristic of mammals is the presence of fur or hair (C). While other options like eyes (A), four limbs (B), or tails (D) are common in many animal groups, fur is unique to mammals.
Eyes are found in nearly all vertebrates and invertebrates, limbs are shared with reptiles/amphibians, and tails appear in birds/reptiles. Thus, the correct answer is C (Fur), as it is exclusive to mammals.