AP Biology Ch 34 Animals Protostomes

The correct answer is "head, thorax, and abdomen." Insects have a distinct body structure consisting of three main parts. The head contains the sensory organs, such as the eyes, antennae, and mouthparts. The thorax is the middle section of the body and is responsible for locomotion, housing the legs and wings. The abdomen is the posterior part of the body and contains the digestive, reproductive, and respiratory systems. This division of body parts is a defining characteristic of insects and is essential for their survival and functioning.

The correct answer is radula. The passage states that the snails use a toothlike rasping organ in their head to scrape up porous limestone and digest the algae. The radula is a specialized feeding organ found in mollusks, including snails, that is used for scraping and rasping food particles. Therefore, the radula is the most suitable organ for the described behavior of the snails.

The octopus is considered the most intelligent of the invertebrates due to its complex problem-solving abilities, advanced learning capabilities, and impressive memory skills. Octopuses have been observed using tools, exhibiting curiosity and creativity, and even displaying signs of playfulness. They have a highly developed nervous system and can adapt their behavior to different situations, making them highly adaptable and intelligent creatures.

Protostomes and deuterostomes are similar in that they both form a hollow sphere in the embryo that has an indentation called a blastopore. This blastopore eventually develops into either the mouth or the anus, depending on the organism. This is a key characteristic in the early development of both protostomes and deuterostomes, and it helps to differentiate them from other types of embryos. The other statements provided in the question are not accurate descriptions of the similarities between protostomes and deuterostomes.

Arthropoda is the correct answer because it is the largest phylum in the animal kingdom, comprising over 80% of all known animal species. This phylum includes insects, spiders, crustaceans, and other arthropods. They are characterized by having jointed limbs and a hard exoskeleton. Mollusca, Chordata, Echinodermata, and Annelida are also phyla, but they have fewer species compared to Arthropoda.

Millipedes differ from centipedes in multiple ways. Firstly, centipedes generally have fewer legs per segment compared to millipedes. Additionally, millipedes are herbivorous, while centipedes are carnivorous. Lastly, while large centipedes can be dangerous to handle, millipedes are considered safe. Therefore, all of the above statements are correct in explaining the differences between millipedes and centipedes.

An insect circulatory system is best described as an open system that mostly washes "blood" through the body cavities. Unlike our closed circulatory system with distinct arteries and veins, insects have a network of small tubes called tracheae that transport oxygen directly to their body tissues. Insects also have a tubular heart that pumps a fluid called hemolymph into the body cavity, where it bathes the organs and tissues. This hemolymph transports nutrients and waste products, but it does not circulate in a closed loop like our blood. Therefore, the correct answer is an open system that mostly washes "blood" through the body cavities.

Earthworms use chitinous bristles called setae to anchor themselves in the earth and move along. Setae are located on the ventral side of their body and are used for locomotion. They help the earthworm grip the soil and create traction as it contracts and expands its muscles, allowing it to move forward or backward. The other options listed, such as aortic arches, lateral ventricles, parapodia, and nephridia, are not related to the chitinous bristles used by earthworms for movement and anchoring.

A closed circulatory system is a type of circulatory system where the blood is contained within vessels and does not directly come into contact with the body tissues. Insects, snails, clams, and scorpions have an open circulatory system, where the blood is not contained within vessels and directly bathes the body tissues. However, earthworms have a closed circulatory system, where the blood is contained within vessels and is circulated throughout the body.

Having a true coelom provides several advantages, such as the ability to store sperm and eggs before they are released, the coiling of the digestive system to increase surface area, the assistance of fluids in respiration and circulation, and the protection of complex organ systems from damage and temperature changes. However, muscle contractions against the fluid chambers in a true coelom are not absorbed and have no effect, which means they do not contribute to any of the aforementioned advantages.

The characteristic "swimming larvae are found in all forms" is not found in the class Gastropoda. This class of mollusks typically does not have swimming larvae.