Lower animals & Invertebrates

31. What is the body plan of a sea urchin?

a) Bilateral symmetry

b) Radial symmetry

c) Asymmetrical

d) Spherical

32. How do sponges reproduce?

a) By laying eggs

b) By live births

c) By budding

d) By pollination

33. Which of the following is not a characteristic of arthropods?

a) They have jointed appendages

b) They have a segmented body

c) They have an exoskeleton

d) They have a closed circulatory system

34. What is the phylum of animals that includes insects and spiders?

a) Porifera

b) Mollusca

c) Arthropoda

d) Echinodermata

35. How do mollusks respire?

a) Through gills

b) Through lungs

c) Through spiracles

d) Through their skin