BIO 109 Home
Questions | Answers

1. Phylum Arthropoda: have jointed legs and an exoskeleton. Includes insects, arachnids, crustaceans, millipedes, and centipedes, among others.

2. 86%

3. Insects have 3 body parts (head, thorax, abdomen), 6 legs, and 1 pair of antennae. Beetles, flies, ants, butterflies, grasshoppers, etc. are insects.

4. Arachnids have 1 or 2 body parts (cephalothorax, abdomen), 8 legs, no antennae. Spiders, scorpions, ticks, and mites are arachnids.

5. The hard (usually) outer covering of arthropods that function as their skeleton in providing support and protection.

6. Incomplete Metamorphosis: egg, nymph (looks like adult), adult. Grasshoppers, cockroaches, etc.
Complete Metamorphosis: egg, larva (does not look like adult; e.g., caterpillar), pupa, adult. Butterlies, flies, ants, beetles, etc.

7. Advantage: larva and adult can specialize in form for their different functions (eating vs reproducing). Also larva and adult don't usually compete for food resources.
Disadvantage: Pupal stage is vulnerable.

8. Spiracles (holes through the exoskeleton) lead into tracheae that extend throughout the body bringing fresh air directly to all the tissues. This tracheal system of respiration brings air directly to the tissues rather than having to first diffuse into a circulatory system and then get pumped around the body.

9. They attack from farther away from their hive, they get mad faster, more come out at once to attack, and they stay mad longer. This results in the victim getting more stings. Note: each bee can only sting one time and the sting of an Africanized bee is no more dangerous than a European bee.

10. The selection pressure would be that African honey bees suffer greater rates of predation compared to European honey bees because in Africa the predators are led to the hive by the Honeyguide Bird. In Europe, if the honey bees remain calm and quiet then the predator usually passes by without detecting the hive.

11. Round dance: bee dances in circle with food in its mouth, indicating to the other bees that this particular food source is close to the hive.
Waggle dance: bee dances in figure 8, indicating to the other bees the distance and direction to the food source that is farther away. Distance is indicated by how long it take the bee to do one circuit of the dance. Direction is indicated by the direction the bee wags in when it does the straight part of the dance between the two circle. The direction is given relative to the direction of the sun. Dancing straight up the hive indicates go toward sun. Dancing downward indicates the food is away from the sun. Dancing to the left or right of up indicates the food is to the left or right of the sun (see PowerPoint for practice being a bee).