BIOB34H3 Lecture 1: What are Animals
Document Summary
There are lots of anatomical and physiological diversity in the animal kingdom. Insects (e. g. ants) are animals: 75% of all known animals are insects. Sponges are animals: some believe they are the ancestor of animals. Sea urchins, sea stars, sea cucumbers are animals (not plants: part of the phylum echinoderms, closest invertebrate group to vertebrates, development is more like vertebrate groups. Rotifers are the smallest animal (less than 1 mm: commonly found in pond water. Blue whales are the largest animal: also the largest known organism. Cnidarias; nematocysts are used to penetrate and paralyze prey) Two major types of cells; prokaryotic and eukaryotic. Prokaryotic cells have no nucleus: they have a singular loop of dna, lack organelles. Eukaryotic cells have a nucleus: nucleus houses dna in linear pieces called chromosomes, have organelles. Not a defining feature of animals because plants, fungi, protists are eukaryotic: animals are eukaryotic but not all eukaryotes are animals.
