Taxonomy

Question 1

what is meant by the term systematics

Answer 1

the study of interrelationship between species

Question 2

define phylogeny

Answer 2

the evolutionary history of a species

Question 3

what is meant by the term cladistics

Answer 3

an examination of the order in which organisms evolved producing phylogenic trees called cladograms

Question 4

what is the difference between monophylogeny and paraphylogeny

Answer 4

mono = a single common ancestor
para= a single common ancestor which is far removed

Question 5

what is the traditional method of producing cladograms to study evolution

Answer 5

by examining the structure/morphology of fossils

Question 6

what is an issue of using fossils to study the evolution of organisms

Answer 6

some tissues fossilize better than others, therefore, the fossil produces an incomplete picture of the organisms

Question 7

what is a more modern and updated version of studying the evolution of organisms

Answer 7

looking at the molecular level such as mutations or genetics

Question 8

what is a molecular clock

Answer 8

a term used for a technique that uses the mutation rate of biomolecules to deduce the time in history when two or more lifeforms diverged

Question 9

what is the most likely organism in which animals first evolved form

Answer 9

choanoflagellates which are simple protists in which all cells function similarly and separately (colonial cells)

Question 10

what was the name of the person who compared embryonic development in different animals to develop theories of animal evolution

Answer 10

Haeckel

Question 11

how do animals differ from choanoflagellates

Answer 11

1) multicellularity
2) germ cells
3) collagen

Question 12

what are the different stages of evolution causing differentiation in species

Answer 12

1) tissues
2) bilateral symmetry
3) protostome development
4) lophophore or trochophore larva
5) deuterostome development

Question 13

what is the difference between parazoa and eumetazoa animals

Answer 13

1) animals with no tissue differentiations i.e. cells perform similar functions
2) all other animals with true tissues

Question 14

give some examples of parazoa species

Answer 14

1) porifera= sponges
2) placozoa = flat animals

Question 15

what are radiata

Answer 15

a taxonomic ranks of animals with radial symmetry = multiple planes would produce symmetry compared to bilateral animals in which only one plane produces symmetry

Question 16

give some example of radiata species

Answer 16

1) cnidaria = hydra, jellyfish etc
2) ctenophora= comb jellies

Question 17

what is meant by the term diploblastic

Answer 17

two layers = the ectoderm and the endoderm

Question 18

what is meant by the term triploblastic

Answer 18

has three layers = ectoderm, mesoderm and endoderm

Question 19

what are the 3 further classifications based on how the mesoderm is organised in the body other than diploblastic and triploblastic

Answer 19

coelomate animals= all organs lined by mesoderm
pseudocoelomate animals = some organs lined with mesoderm
acloelomate animals = no mesoderm, just a solid mass of tissues

Question 20

what ate some of the characteristics of parazoa

Answer 20

• no tissues or organs
• come between colonial protists and metazoans
• consist of two phyla; porifera and placozoa

Question 21

what are placozoa

Answer 21

one of two phyla in parazoa with the simiplest structures = flat animals

Question 22

what are proifera

Answer 22

one of two phyla in the parazoa which are sessile organsism with porus bodies (sponges)

Question 23

what are the three basic body plans of sponges (porifera)

Answer 23

1) asconoid= simplest radial form tubular in shape
2) syconoid = more elaborate foldings of the body wall
3) leuconoid = highly folded and posses flagellated chambers

Question 24

what are the four classes of sponges/porifera

Answer 24

1) calcarea
2) hexactinellidae
3) demospongiae
4) homoscleromorpha
refer to powerpoint for characteristics of each