Lecture 2

Question 1

what are the 4 eukarya supergroups?

Answer 1

-excavata
-SAR
-archaeplastida
-unikonta

Question 2

what does SAR contain?

Answer 2

-stramenopile
-alveolate
-rhizaria

Question 3

what are the two major clades apart of the unikonta?

Answer 3

-amoebozoans
-opisthokonts

Question 4

what are some examples of species within the amoebozoans? what is a key feature of these species?

Answer 4

-slime moulds
-amoeba
-have lobular pseudopodia

Question 5

what is lobular pseudiopodia?

Answer 5

-lobular protrusions (feet)

Question 6

what are some examples of species within the opisthokonts?

Answer 6

-animals
-fungi
-closely related protist groups

Question 7

what are examples of typical animal characteristics?

Answer 7

-multicellular
-no cell walls (plasma membrane)
-can move
-heterotrophic
-embryonic tissue

Question 8

what junctions are present in animals? what is the purpose of these junctions?

Answer 8

-gap junctions (communication)
-tight junctions (hold/interconnection)

Question 9

why is movement important in animals?

Answer 9

-need directional motion to seek for new habitats in case of stressful environments
-survival (predation)
-find food + water
-find mates (reproduction)

Question 10

what does it mean to be heterothrophic?

Answer 10

-obtain energy from energy releasing foods/substances
-cannot produce their own food

Question 11

what are the 3 embryonic tissues?

Answer 11

-endoderm
-mesoderm
-ectoderm

Question 12

what are the basic concepts of the animal life cycle?

Answer 12

-have a diplontic life cycle
-form from gametes into a zygote
-have a juvenile and adult form

Question 13

what does is mean to have a diplontic life cycle?

Answer 13

-to have a lifestyle that is dominated by the diploid stage

Question 14

what are the male and female gametes? are they haploid or diploid?

Answer 14

-sperm (male)
-egg (female)
-diploid

Question 15

what occurs between the juvenile and adult forms of an animal? what is an example of an animal that goes through this?

Answer 15

-a stage of change called metamorphosis
-tadpole + frog

Question 16

what is multicellularity used to describe?

Answer 16

-an organism that is composed of many cells

Question 17

what advantages does multicellularity have?

Answer 17

-adds complexity to forms and processes
-allows organisms to survive and thrive

Question 18

where did multicellularity first develop? what clade is closely related?

Answer 18

-first developed in metazoa
-closely related to animalia

Question 19

what did the cells of multicellular organism resemble?

Answer 19

-the single celled choanoflagellates

Question 20

what does the ectoderm form?

Answer 20

-epidermis

Question 21

what does the endoderm form?

Answer 21

-interior organs and muscle systems
-inner cells help form gastrula (gastrovascular cavity)

Question 22

what is the best outgroup for the animal clade?

Answer 22

-porifera (shared common ancestor)

Question 23

what are 3 key features of choanoflagellates?

Answer 23

-have a flagella
-have a collar of microtubules
-live in colonies

Question 24

what is the evidence that supports the evolution of multicellularity from choanoflagellates?

Answer 24

-similar cell morphology (shape, structure, form, size) -unique animal cell morphology (no cell wall + no plastids) -DNA sequence homology

Question 25

what are plastids?

Answer 25

-small organelles containing pigment or food (chloroplasts)

Question 26

what are the key aspects of the porifera phylum?

Answer 26

-known as the sponges -2 main cell layers + a middle region -have random growth (asymmetrical)

Question 26

what are the two cell layers found in porifera?

Answer 26

-epidermis -choanoderm

Question 27

what is the purpose of the choanoderm layer in porifera?

Answer 27

-draws in food particles to be passed through amoebocytes

Question 28

what is found in the middle region of porifera?

Answer 28

-porocytes -mesohyl

Question 29

what is the function of porocytes?

Answer 29

-control the water entering the spongocoel (large central cavity)

Question 30

what is contained within mesohyl/

Answer 30

-amoebocytes -hardened spicules

Question 31

what is a special characteristic of sponges?

Answer 31

-have totipotent cells -a single sponge cell can create a new sponge

Question 32

what are totipotent cells?

Answer 32

-cells that can differentiate into different cell types -ability to self organize -reassembling is spontaneous

Question 33

what much be provided in order for reorganization to occur within totipotent cells?

Answer 33

-lots of activity

Question 34

what do sponges lack?

Answer 34

-radial symmetry -true tissues

Question 35

what does it mean to not have true tissues?

Answer 35

-no organs -no muscles -no nervous system

Question 36

what are the key aspects of the cnidaria phylum?

Answer 36

-diploblastic -have radial symmetry -can have 2 body shapes

Question 37

what does it mean for an organism to be diploblastic?

Answer 37

-they have 2 embryonic germ layers (2 tissue systems) -only have an endoderm and ectoderm

Question 38

what is the purpose of the ectoderm in development?

Answer 38

-covers the surface of the embryo

Question 39

what is the purpose of the endoderm in development?

Answer 39

-lines the pouch formed during gastrulation -lining of the digestive tract, liver, and lungs

Question 40

what are the 2 cellular layers and the 1 non-cellular layer of the cnidaria phylum?

Answer 40

-epidermis + gastrodermis = cellular -mesoglea (jelly) = non-cellular

Question 41

what are the 2 body shapes that can be taken on in the cnidaria phylum?

Answer 41

-polyp form -medusa form

Question 42

what species take on the polyp body form? what are the basic aspects?

Answer 42

-anemones + hydras (crawling animals) -cylindrical -mouth/anus faces up -aboral side is for movement

Question 43

what species take on the medusa body form? what are the basic aspects?

Answer 43

-free swimming jellys (free moving animals) -bell shape -mouth/anus faces down -tentacles point down

Question 44

what is radial symmetry? what are its key aspects?

Answer 44

-several planes of symmetry around 1 central body axis -no right or left side -have a top + bottom

Question 45

what is the top side of an radial species referred to as?

Answer 45

-oral side (mouth and anus)

Question 46

what is the bottom side of a radial species referred to as?

Answer 46

-aboral side (furthest from mouth)

Question 47

where did radial symmetry first evolve?

Answer 47

-cnidaria phylum

Question 48

what are tissues?

Answer 48

-groups of specialized cells that perform a specific function -can be isolated from other tissues by membranous layers

Question 49

how many groups, systems, and membrane layers of tissues do parazoa have?

Answer 49

-1 group -1 system -no membranes

Question 50

how many groups, systems, and membrane layers of tissues do eumetazoa have?

Answer 50

-1 group -2 systems -membranes

Question 51

what two major events formed eumetazoan tissues?

Answer 51

-cleavage -gastrulation

Question 52

what is cleavage?

Answer 52

-numerous mitotic divisions

Question 53

what does gastrulation form?

Answer 53

-primitive gut (primary digestive tube) -blastopore (mouth)

Question 54

what 2 embryonic germ tissues do eumetazoans have?

Answer 54

-ectoderm (outer layer) -endoderm (inner layer)

Question 55

what does it mean for an organism to be triploblastic?

Answer 55

-have 3 germ layers (3 tissue systems) -ectoderm, mesoderm, endoderm

Question 56

what is the purpose of the mesoderm?

Answer 56

-fills the space between the ectoderm + endoderm -forms muscles + most inner organs

Question 57

what are examples of organisms who are triploblastic?

Answer 57

-flatworms -arthropods -vertebrates

Question 58

what are grades of organization?

Answer 58

-organisms that only share key biological features -no relationship between organisms -a result of convergent evolution

Question 59

what is the reason for grades of organization? how do they arise?

Answer 59

-develop to overcome obstacles -when 2 unrelated groups have found a similar solution to their own unique problems

Question 60

what are examples of grades of organization?

Answer 60

-coelom -segmentation -wings