Biology Chapter 28 Flashcards
1
Q
What are the 6 criteria for classification?
A
1) The number of germ layers
2) Body symmetry
3) Body Plan
4) Type of coelom
5) Segmentation and HOX genes
6) Molecular data
2
Q
What is a germ layer?
A
Primary tissue layer in vertebrates
3
Q
How many germ layers are there? Name them.
A
There are 3.
Ectoderm - outter most layer
Mesoderm - middle layer
Endoderm - inner layer
4
Q
Animals can have ____, ____, or _____ germ layers
A
None - sponge
2- jelly fish
3 -flat worms and all other animals.
5
Q
What are the 3 types of symmetry?
A
Asymmetrical
Radial Symmetry
Bilateral Symmetry
6
Q
What is Aysmmetrical symmetry?
A
you cannot cut it or rotate it to obtain identical parts of the whole animal.
7
Q
What is Radial Symmetry?
A
The animal is symmetric if rotated on a set point.
8
Q
What is Bilateral Symmetry?
A
Identical left and right halves. Always has a head.
9
Q
What is cephalization?
A
The formation of a head.
10
Q
How many animal phyla are there currently?
A
35
11
Q
What is a body plan?
A
it is the entrance and exit of food and waste.
“digestive system”
12
Q
How many types of body plans are there?
Name them
A
2.
Sac body plan and Tube plan.
13
Q
How does a sac body plan operate?
Is it complete or incomplete?
A
incomplete. Food and waste enter and exit out of the same hole.
14
Q
how does a tube body plan operate?
is it complete or incomplete?
A
complete. food enters one hole and leaves through a separate one.
15
Q
What is a coelom?
A
a body cavity that is isolated from the digestive tract and holds organs and fluid.
16
Q
Why would an animal not be considered a “true” celomaete?
A
The animal may not be considered a true celomaete unless the body cavity is isolated from the digestive tract.
17
Q
What are the three types of coelom grouping and what are their discriptions?
A
~acoelomate: no coelom
~pseudocoelomate: has a body cavity but it is not isolated from the digestive tract
~Coelomate: has coelom that is isolated from the digestive tract.
18
Q
If the mouth develops first the animal is called a:
A
Protostome
19
Q
If the anus develops first the animal is called a:
A
deuterostome.
20
Q
What do HOX genes encode?
A
Homeotic Proteins
21
Q
What do HOX genes orchestrate?
A
The developmental fate of a particular region of the body
22
Q
How are HOX genes different for animals with a simple body plan vs an animal with a complex body plan?
A
Simple body plans have less HOX genes
Complex body plans have more.
23
Q
What does the colonial flagellate hypothesis state?
A
That all animals are descended from an ancestor that resembled a hollow spherical colony of flagellated cells.
24
Q
The Colonial flagellate hypothesis is a hypothesis on:
A
how multicellularity may have evolved.
25
What are the 4 steps described in the colonial flagellate hypothesis to multicellularity?
1- single motile flagellates form an aggregate (bundle of cells)
2- colony of cells form a hollow sphere.
3- specific cells begin to specialize for reproduction.
4- the hollow colony infolds which creates tissue layers.
26
Which protist is the closest living relative to all animals?
Chanoflagellates
27
How do we know that chanoflagellates are the protist that is most closely related to all animals?
DNA
28
What protist is considered to be the common ancestor of multicellular animals?
chanoflagellates.
29
Name the 9 invertebrate phylums.
- Porifera -Arthropoda
- Cnidarian -Echinodermata
- Platyhelmenthes - Rotifera
- Nematoda -Mollusca
- Annelida
30
What are the characteristics of Phylum Porifera?
- organized group of cells (no tissues or organs)
- no germ layers
- acoelmates (no body cavity)
- asymmetrical
- sac body plan
31
What are the characteristics of Phylum Porifera?
Name an animal in this phylum.
- organized group of cells (no tissues or organs)
- no germ layers
- acoelmates (no body cavity)
- asymmetrical
- sac body plan
Sponges
32
What are the 3 main cell types found in sponges?
Choanocyte, amoebocyte and epithelial cells.
33
In a sponge, what do the choanocytes provide?
choanocytes (have a collar and flagella) move water currents and trap food for the sponge
34
In a sponge what do the amoebocytes contribute?
amoebocytes are attached to the choanocytes and digest food
35
In a sponge what do the epithelial cells contribute?
the epithelial cells make up the "body" of the sponge.
36
List the 2 types of sponge skeletons and describe what they are made of.
Spicules- 3 pronged silica or limestone spikes that overlap
| spongin: tough flexible protein fibers.
37
what are the differences in the adult and larval stages of sponges?
larvae are flagellated and free swimming
| adults forms are sessile (anchored to a substrate)
38
What animals are included in the Phylum cnidaria?
Jellyfish, coral, sea anemone
39
What are the characteristics of animals in the Phylum Cnidaria?
- Sac body plan
- Radial symmetry
- acoelomate
- True tissue layers: epidermis and gastrodermis
- 2 germ layers: ectoderm and endoderm
40
Dimorphic
an organism with two body shapes in its life cycle.
41
What are the two body shapes that cnidarians can have?
```
Polyp (sessile)
or medusa (free floating)
```
42
Cnidaria are the only phylum in the animal kingdom to have:
Cnidoblasts that contain nematocycts (toxic harpons)
43
what is the translucent gel-like substance that makes up a jellyfish?
Mesoglea
44
what liquids should you use to remove nematocysts from skin?
Vinegar or sea water
45
what liquids should you NOT use to remove nematocysts from skin?
fresh water or urine
46
What marine animals eat jellyfish?
leatherback sea turtles
ocean sunfish
lobster larvae
nudybranks
47
what is a baby jellyfish called?
efferie
48
Sea aneomne have what body shape ONLY
polyp
49
Sea anemones have a ____ relationship with ___ and ___
symbiotic; many green algae and fish
50
What body shape make up corals?
polyps
51
What chemical do corals deposit to build the reef?
calcium carbonate (limestone)
52
What word is used to describe the algae that live symbiotically with the corals?
zooxanthellae
53
What do zooxanthella provide the coral?
oxygen, sugar and fats
54
what do the coral provide the zooxanthella?
carbon dioxide and nitrogen
55
what is a siphonophore?
it is a group of polyps that have different jobs but cooperate
56
what are the different jobs that polyps can have?
float (substrate), feeding, reproduction, or movement
57
T/F all jelly fish are large enough to see with the naked eye?
false. Some are microscopic others are larger than a human.
58
T/F global climate change is causing a surge in the jellyfish population?
True
59
What are the characteristics of the phylum platyhelminthes?
What animals are in this phylum?
-acoelomates
-sac body plan
-3 germ layers
-organs
-Bilateral symmetry
Flat worms
60
Why are platyhelminthes flat?
They have no respiratory or circulatory system so it must move nutrients and gasses by diffusion.
Diffusion only works efficiently across small surfaces
61
What are the 3 classes in the phylujm Platyhelminthes?
```
Class Turbellaria (flatworms)
Class Trematoda (flukes)
Class Cestoda (tapeworms)
```
62
T/F Turbellaria are parasitic
false they are free living
63
T/F Trematoda are free living?
false they are parasitic
64
T/F Cestoda are parasitic
True
65
```
what is the common name for animals in the class turbellaria?
are they parasitic or free living?
```
Flat worms; free living
66
```
what is the common name for animals in the class trematoda?
are they parasitic or free living?
```
Flukes; parasitic
67
```
what is the common name for animals in the class cestoda?
are they parasitic or free living?
```
tapeworms; parasitic
68
What are the physical characteristics of flatworms?
- Ocelli (eyespots): perceives light only(no images)
- Auricles - chemical sensors
- Gastrovascular cavity
- does not have a brain but doe have a bundle of nerves in the head.
- lateral and transverse nerves
- cerebral ganglia
- pharyngeal chamber
- mouth
- Pharynx (food in waste out)
69
what is the common name of flat worms?
planarian
70
where do Planaria live?
they are free living (non parasitic) in fresh water although some flatworms live on land.
71
how large are flat worms?
generally a few milimeters
72
What is the "superpower that scientists would love to harness from the flatworm?
Regeneration
73
What happens if you cut a planarian into 4 pieces?
each of the 4 segments would grow into a new planarian
74
what type of cells make up 1/5 of the planarians body and what do they allow the planarian to do?
Stem cells; turn into new types of cells and make new body parts
75
what applications in humans would studying planarians help with
the growth of replacement organs and healing of major trauma.
76
How many hosts are in the life cycle of Class Tremotoda (flukes)?
2; usually a primary host vertebrate and a secondary host snail.
77
How are flukes named?
They are usually named after where they infect.
78
Can flukes only infect the body part that they are named after?
no, they can sometimes infect multiple parts of the body.
79
T/F Class Trematoda (Flukes) can be both parasitic and free living
false; they are all parasitic.
80
What is a schistosoma?
A blood fluke common to latin america, the middle east, africa, and asia.
81
what disease does schistosoma cause?
schistosomaiasis; sysentery, anemia, liver/brain damage, and cancer.
82
What is the life cycle of the schistosoma?
1 the larvae penetrates the skin of a human (walking in unsanitary water) and matures in the liver.
2 adult worms live and copulate in the blood vessels of the human gut
3 eggs migrate to digestive tract and are passed via feces.
4 larvae hatch in the water and enter the seonary host (snail)
5 in the sail a mother sporocyst encloses many developing daughter sporocysts . daugher cysts house developing larvae.
6 larvae break out of cysts, escape snail and enter water.
83
Where in the body do schistosoma worms mate?
blood vessels
84
what happens to schistosoma eggs that are laid in a human body?
lodge in bladder and entestines encased in granulmn
85
Why is schistosomisis also called snail fever
larvae incubate in freshwater snails.
86
how does the schistosoma larvae parasite get from the snail to the human?
after leaving the snail and entering the water the larvae penitrates the skin of a human usually through a hair follicle
87
Parasitic tapeworms are members of what class
Cestoda
88
What how many and what host(s) are in the cycle of the creatures in the class cestoda?
Primary host: human
| Secondary host: pig/cow
89
What are the segments of a tapeworm called
Proglottid
90
What is the head of a tapeworm called
scolex
91
how does a tapeworm attach to the host?
hooks on its "mouth"
92
T/F the proglottids closest to the Scolex of the worm are the most mature segments
False. the proglottid closest to the scolex are the youngest or immature proglottids
93
what sex can tapeworms be?
they are hermaphrodites
94
How do tapeworms lay eggs?
once the proglottids at the end opposite to the scolex are gravid the segment breaks off and exits the body via fecal matter
95
A tapeworm has an anterior end and a posterior end. Which end has the smallest proglottids and which end has the largest proglottids?
the anterior end has the smallest proglottids.
| the posterior end has the largest proglottids
96
What is inside the larger tapeworm segments?
eggs
97
how do tapeworm segments eventualy leave the human host?
via fecal matter
98
does a tapeworm have a digestive system? why or why not?
no. it does not have intestines. it absorbs nutrients across the body walls
99
The tapeworm video that was watched during the lecture was filmed in what body part?
A human small intestine.
100
Roundworms are part of what phylum?
Nematoda
101
What are the characteristics of the Phylum Nematoda
```
`3 germ layers
`organs
`bilateral symmetry
pseudocoelmates
tube body plan
```
102
T/F Nematodes can be plant parasites.
true
103
Why is Caenorhabditis elegans (C. elegans) significant?
- Used as a model organism making it important for studying morphogenesis, aging, and neurological disorders.
- it is the first multicellular organism to have its genome sequenced.
- all 959 cells in an adult have been carefully tracked.
104
What doe C. elegans eat in the wild vs the lab
general bacteria; e.coli
105
what are the two forms that C. elegans can develop into?
male or hermaphrodite
106
How many cells do male C. elegans vs hermaphrodite C. elegans have?
males 1031
| hermaphrodite 959
107
how many neurons does c elegans have?
302
108
what types of behaviors do C. elegans present?
Primitive: feeding, locomotion, etc
Complex: mating, social interaction, reactions to chemicals.
109
T/F Nematodes cannot parasitize insect larvae
false nematodes can parasitize insect larvae.
110
Other than C. elegans. Name two other common types of nematodes
Heartworms in dogs
| Pinworms in children
111
Trichinella is a nematode tha can be found in what
infected pork
112
What is significant about the nematode ascaris?
- largest human intestinal parasite
- est 1.2 bill ppl infected world wide
- infection due to poor sanitation (accidental)
- infects: intestines, lungs and stomach.
113
"wheel bearer" is in what phlyum?
Phylum Rotifera
114
T/F Rotifera are protists.
| If false, why.
false. they are tiny but are/have
-3 germ layers
-organs
bilateral symmetry
-multicellular
-pseudocoelomates
-tube body plan
115
Where are cilia found on rotifers?
on the corona
116
What is the function of the cilia on the corona of rotifers
to spin moving food into the mouth
117
how large are rotifers
200-500 micrometers
118
where are you most likely to find rotifers
mostly fresh water some marine specifically where scum is accumulating. occasionally you will locate them on moss.
119
what do rotifers eat?
they are omnivores. they eat small particles of decaying material, algae, and occasionally cannabilize.
120
Characteristics of the Phylum Mollusca
-coelom; 3 germ layers (triploblast); complete digestive tract; organ systems; ingestive heterotrophs; Protostomes;
121
What are the 4 features that unite the invertebrates in Phylum Molluska?
Visceral mass which functions as internal organs
Foot which is a lg muscle for movement or attachement
Mantle which is a fold of tissue that drapes over the visceral mass (note this can secrete a shell in some organisms)
Radula scraping tongue-like organ that scoops food in ( not this is not found in all mollusks.
122
Were are members of the Phylum molluska found?
mostly marine, occasionally fresh water or damp soil.
123
T/F Molluska members are bilaterally semmetric and have an unsegmented body
true
124
List the classes in the Phylum Mollusca
Polyplacophora; Gastropoda; Bivalvia; Cephalopoda
125
List the characteristics of the class polyplacophora
all of the features and characteristics of the phylum mollusca + only marine; Shell w/ 8 plates, strong foot, Radula; no head
126
What is the common name of polyplacophora?
Chiton
127
What is an example of an organism in the class gastropoda?
slugs, snails, nudibranchs
128
Where can you find members of the class gastropoda?
land, fresh or marine water
129
What are the characteristics of the class gastropoda
The characteristics of the phylum mollusca + radula, head w/ tentacles, shell and no shell, gills or lungs
130
How and why do nudibranchs steal nematocysts from cnidarians?
they eat them and store them in to skin of spike to deter predators'
131
Why do many nudipranchs have a striking coloration?
to advertise toxcisity
132
aside from just discovering new species, what are some other reasons to study nudipranchs?
Chemical compounds for pharmaceuticals.
