Biology 11 - L.S.

At the top of the hill of Kensington Park, the time reads 8:58 PM. As the sun sets, the few strips of clouds on the horizon drifts over the mountains, shimmering gold. The golden glow tears across the clear, deep blue sky as if it was crying for attention. There is a cool and gentle breeze that is just strong enough to let my hair flutter through the wind. Chilling goosebumps form on my bare arms. I inhale a breath of fresh air and slowly let it out. It is a crisp and soothing scent – the natural, faint smell of Earth itself. People on the field enjoying the last bits of light left in the sky. Some are packing up and getting ready to return to their homes, while some lay still on the soft grass and stare into space. I myself lay on my mat and study the area that gives me aesthetic pleasure. I run my fingers through the slightly damp grass as I listen to the subtle, chill house music playing from my speaker. A couple of dogs are running around – using the remaining amount of energy l

Keeping Up with the Cnidarians SCENE 1 NARRATOR In the Kingdom Animalia, Phylum Cnidaria includes the group of soft bodied animals with stinging tentacles called “nematocysts”. Their symmetry is radial, and they mainly compose of having a mouth and stomach. They swim around and catch food in their marine habitat. They have three layers; the epidermis, which is the outer skin; the endoderm, which is their gut or stomach and their mouth; and the middle part is the jelly, the mesoglea. They kill their prey with nematocysts. Even if the animal is dead, the nematocysts still work because they are spring-loaded to fire off and stun the prey. There are three classes of Cnidarians: Hydrozoa, Scyphozoa, and Anthozoa. Today, we are going to have our first encounter with the three most famous Cnidarians. SCENE 2 NARRATOR We are about to see the home of one of the Cnidarians. This is an exclusive opportunity to get to see the life of an A-lister celebrity. (cut to Hydra’s house)

Overview of Kingdom Animalia  Multicellular eukaryotic heterotrophs with no cell walls and their own fates Ninety-seven percent invertebrates and only three percent vertebrates Radial is one type of symmetry for a living organism But don’t exclude bilateral symmetry because we are not fond of criticism Primitive animals are not as specialized as more recent ones are involved They don’t have a body cavity and their mesoderm is not evolved Recent animals possess a concentration of nerves in the area of the head While primitives have either no nervous system or they have a neutral net instead Keep in mind that the animals who tend to show radial symmetry came first And current animals exhibit bilateral symmetry even at their worst Subkingdom Parazoa has organisms that have simple cells, no organs and specialized tissues according to their classification Whereas members of subkingdom Metazoa carry a complex, multicellular and structural organization The stages of development