Invertebrate Zoology

Earthworms have 5 pairs of aortic arches that function like hearts, commonly referred to as '5 hearts' in educational materials. These structures pump blood through the worm's circulatory system. Options A (0), B (1), and D (7) are incorrect.

Butterflies undergo complete metamorphosis: egg → larva (caterpillar) → pupa (chrysalis) → adult butterfly. The caterpillar is the feeding and growth stage before transformation.

Periplaneta americana is the scientific name for the American cockroach species. The other options represent: Musca domestica (housefly), Canis familiaris (domestic dog), Naja naja (Indian cobra), and Bombyx mori (silkworm).

Earthworms do not possess true eyes or eyespots. Instead, they have light-sensitive cells (photoreceptors) distributed throughout their skin, particularly concentrated in their anterior segment, which allow them to detect light intensity and help them avoid exposure to daylight.

This is true. Cockroaches can survive approximately a week without their head because they breathe through spiracles (small openings) on their body segments, not through their mouth or nose. They eventually die from dehydration or inability to eat, not from loss of the head itself.

Cockroaches can survive approximately 9 days without their heads because they breathe through spiracles (small openings) on their body segments, not through their mouth or nose. They eventually die from dehydration or starvation since they cannot eat or drink without their head.

Cockroaches can survive for weeks without their heads because they have an open circulatory system and breathe through spiracles located on their body segments. Their nerve clusters can still function independently, allowing basic movements and reactions. Option B (9 days) represents a commonly cited duration in scientific trivia.

Cockroaches have a 13-chambered tubular heart. This is a specialized anatomical fact in invertebrate biology. The other chamber numbers (11, 12, 14) are incorrect.

Earthworms have 5 hearts (aortic arches) that pump blood through their circulatory system. This is a well-known biological fact taught in basic science education.

Cockroaches breathe through spiracles (tiny pores) along their body segments, not through their mouth or head. This allows them to survive for days without a head, though they eventually die from dehydration or inability to eat.

A cockroach's brain is actually located in its head, not outside its body. The nervous system is distributed throughout the body with ganglia, but the brain itself is in the head.

The Megaloblatta longipennis cockroach species, found in Central and South America, is indeed one of the largest cockroaches, with some specimens reaching up to 6 inches in body length and having a wingspan that can approach one foot. This makes the statement factually accurate.

Cockroaches have a distributed nervous system with nerve ganglia throughout their body, so they don't rely solely on their brain for essential functions. They can survive for approximately one week (and sometimes longer) without their heads because they breathe through spiracles along their body and can continue basic motor functions. The statement is scientifically accurate.

This statement is TRUE. Cockroaches can indeed hold their breath for up to 40 minutes, and they can survive underwater for about 30 minutes. They breathe through small openings called spiracles on their body segments, and they can close these to conserve water and survive in low-oxygen environments.

Earthworms lack eyes entirely. They have light-sensitive cells scattered in their epidermis, particularly concentrated at the anterior (front) end, which allow them to detect light intensity and direction. This helps them avoid exposure to damaging light, but they cannot form visual images.