Chapter+18

Chapter 18 Questions

1. I filicinophyta II bryophyta III filicinophyta IV angiospermophyta V coniferophyta VI angiospermophyta VII bryophyta VIII coniferophyta

2. a) 1 and or 34 b) 24 - 33 c) 1 - 23 d) all the species e) 8 more is more closely related to species 16 as they belong to the same family, but with 6 they are different family but same order where the differences are more than at the family level. f) it is the only representative species in the genus, family and order.

3.a) Distinguish between using externally recognition features b.) __Compare__ external recognition features
 * **porifera** || **mollusca** ||
 * assymetrical || bilaterally symmetrical ||
 * no mouth,one excurrent opening || oral and anal pores present ||
 * internal spicules present || external shells in most ||
 * simple body || differentiated in organs and systems ||
 * no eyes || simple or complex eyes ||
 * **annelida**

segmented soft body || **arthropoda**

segmented hard body || chaetae(bristles) || jointed limbs/appendages || c) Compare external recognition features 4. a) Kingdom - Animalia Phylum - Chordata Class - Mammalia Order - Primates Family - Hominidae Genus - Homo Species - //Homo sapiens//
 * hydrostatic skeleton || jointed exoskeleton ||
 * no eyes || compound and simple eyes ||
 * hermaphroditic || dioecious except aphids which carry out parthenogenesis (externally detectible?) ||
 * no jointed limbs,
 * no eyes || compound and simple eyes ||
 * **cnidaria** || **platyhelminthes** ||
 * radial symmetry || bilateral symmetry ||
 * acoelomate || pseudocoelomates (external recognition?) ||
 * tentacles around the oral opening || oral opening with no tentacles ||
 * stinging cells || no stinging cells ||
 * two distinct body forms in life || body shape always wormlike ||

b) Binomial system outline
 * it is a system that awards a living organism two part names
 * first is the generic name from the genus and the second part the specific epithet gives a description about the organism
 * both names are italicized if in print text and underlined or written in different colour of ink in handwritten text.
 * the initial letter of the generic name is capitalized and the rest of the names written in lower case.
 * sometimes the article for the name is followed by the last name of the person who named the organism.
 * when used with the common name the scientific name follows in parentheses.
 * where scientific name has been used elsewhere in the text the generic name may be abbreviated after the first mention.
 * the name is usually made to sound Latin or Greek

c)designing Biological key
 * at each level one characteristic is considered and two alternative forms of the trait designated.
 * when a characterisitic describes only one organism the organism is identified at that level.
 * when the characteristics describes more than one organism it leads to another step.
 * the opening statement must be fully described before the following alternative can be started
 * for a correctly drawn dichotomous key the number of steps is always 1 (more than ?) the number of organisms.