Unit 2 pt.3 Flashcards
lecture 17 - (103 cards)
1
Q
How did animals manage to protect vulnerable stages?
A
Putting zygotes in eggs or in uterus
2
Q
How did animals withstand gravity?
A
staying small or having a strong endoskeleton
3
Q
How did animals conserve and transport water, oxygen, nutrients, and waste?
A
Specialization of terrestrial living:
- skin/exoskeleton
- respiratory system
- digestive system
- circulatory system
- excretory system (kidneys)
4
Q
Sponges’ cellular level organization?
A
- few cell types (choanocytes, amoebocytes, porocytes)
- cells cooperate but don’t form obvious tissues
- pluripotent
- (a)sexual reproduction
- change shapes and regenerate
-no distinct germline (monoblastic ?)
5
Q
Sponge body plan?
A
body plan: made of spicules that are surrounded by protein, spongin, and collagen
6
Q
How do sponges do gas exchange?
A
dissolved gasses are in water and choanoctyes create a current that sucks water through the pores
7
Q
How do sponges feed? And why is this innovative
A
Similar to gas exchange, suck it in through porocytes and food its caught in the collars of the choanocytes
This is the first time we’ve seen feeding happening inside the organism
8
Q
Sponge internal transportation?
A
Water handles a big chunk but amoebocytes do nutrient transport, waste removal, and can transform into other cell types
9
Q
Do sponges have a sensory/nervous system?
A
nope
10
Q
Can sponges move?
A
In little amounts by picking their spicules up and kinda pushing/dragging it along (leaves a trail behind)
11
Q
Cnidaria body plan?
A
- radial
- discrete tissue organization
- diploblastic (ecto = epiderm and other cells, endo = gastrodermis) + mesoglea = jelly substance in da middle (…like a jelly donut)
- two forms: polyp (baby) and medusa (adult)
12
Q
Cell specialization in cnidaria?
A
Here we see Eumetazoans that are specialized to move and eat
- inside are digestive cells and gland cells (for larger prey)
-outside are muscle cells for movement and sensory/ordinary neurons
13
Q
How do cnidaria capture prey?
A
By using cnidocytes (stinging cells) that inject a coiled thread (nematocyst) that contains neurotoxins into prey. This paralyzes them and the muscle cells move the prey into the gut
14
Q
How do cnidaria do gas exchange?
A
- have a low metabolic rate, so don;t need a bunch of input
-surface area allows for gas capture from water
15
Q
How do cnidaria feed?
A
It depends. It can be prey capture, direct absorption of nutrients, digestion (gut cavity and phagocytosis)
16
Q
How do cnidaria do internal transport?
A
One big gastrovascular system with a lot of surface area (folds) that move things around
17
Q
How is the body axis set in cnidarians?
A
By Hox genes, that define gastric pouches (also define somite positions in mice)
18
Q
Do cnidarian have a sensory/response/nervous system?
A
They do have a nervous system but not all condensed in one place its a nerve net (not a brain)
some species have simple eyes
19
Q
How do cnidaria move?
A
“muscles” beat to allow them to move
20
Q
Ctenophore body plan?
A
-biradial
-cilia-bearing plates (combs)
21
Q
Ctenophore gas exchange?
A
High surface area and close water contact
22
Q
Ctenophore feeding?
A
Prey capture with colloblasts: sticky
threads and a through gut
23
Q
Ctenophores internal transport?
A
High surface area
24
Q
Ctenophores Sensory / nervous
system
A
Neural net
25
Ctenophores movement?
Cilia for swimming
26
Summary for basal animals
* All animals: Multicellularity, cell-cell junctions, collagen and
extracellular matrix, a few homeobox genes
* Porifera: Multicellular, but protist-like in many ways
* Basal animals (Cnidaria & Ctenophores):
- Gastrulation - Diploblasty
- Extracellular digestion
- Cnidocytes or colloblasts for prey capture
- Neurons
- Muscle cells for rhythmic movement
27
What are some new things seen with bilateria?
- troploblasty (now includes a "true" muscle and most organs are found within the coelom
- cephalization: condensed neural thing (except echinoderms(...they want to be extra). Means Preferred orientation in space, Directed movement through the
environment, Sense organs and neural integration, and a Mouth!
28
What are the 2 main groups in Lophotrochozoas?
Annelids and molluscs (they have 12-16 other phyla)
29
What are the unifying features between the two groups in lophotrochozoans?
feeding or larval structures have cilia for moving food
30
What is important about annelid diversity?
a lot of variation in body plans of worms due to segmentation
31
Annelid body plan?
- starting to see segmentation (repeating segments - *metamerism* and having different segments with different appearances and functions - *heteronomy*)
- Hox genes for head to butt axis Is also used to identify specific segments
32
Annelid body plan?
- coelom (important for movement)
33
Annelid gas exchange?
- Across a moist surface
- Some have gills or other surface
elaborations
34
Annelid feeding?
- Complete digestive tract
- Specialized regions (e.g., crop
stores food; gizzard grinds food)
35
Annelid internal transport?
- closed circulatory system
- Dorsal “hearts” – contract to push
blood around body
- Blue/red/no blood pigments (carry O2)
36
Annelid Sensory/Nervous systems?
- Ventral nerve cord, several large
ganglia in head = simple brains
- Receptive to wide variety of stimuli, including light
- Simple light-receptive cells to small
lens eyes
37
Annelid movement?
- Hydrostatic skeleton with segmentation
- Segments can change
shape independently
- when the muscles on one side contract, the fluid-filled chamber changes shape and the animal bends
38
How do we see the expansion of Hox genes in annelids?
Hox genes are used to specify the form and function of certain segments and contribute to annelid diversity
39
What is the most diverse phylum of the protostomes?
Mollusca
40
Mollusca Body Plan?
* NOT segmented
* Coelom reduced
* 3-part bodies - muscular foot,
visceral mass (internal organs),
mantle – secretes shell
* Calcium carbonate shell: prominent, reduced, or lost
41
Mollusca Gas Exchange?
- Well-developed gills
in most
- “Lungs” if terrestrial
42
Mollusca feeding?
- Complete digestive tract
- Everything from suspension feeding (e.g. bivalves) to macrocarnivory
-Rasping radula to octopus beak
43
Mollusa internal transportation?
- Circulatory systems (most - open (low pressure) & Cephalopods – closed)
- Blood pigments (Blue – hemocyanin (Cu) is oxygen
carrying protein)
- Well-developed heart(s) (Cephalopods, like a squid or octopus – three hearts: 2 gill hearts and 1 systemic heart)
44
Mollusca Sensory/Nervous systems?
Vary with activity level
- Cephalopods (active predators):
Sophisticated sensory and neural
processing similar to vertebrates!
- Octopus – central brain – 170 million neurons, plus large, semi-independent ganglia in arms – 330 million neurons Intelligence in the protostome body plan
- Convergent: camera style eye with lens
45
Mollusca movement?
- Many use foot (foot also evolved into propolsive device in some)
46
Main groups in edysozoa and unifying feature?
nematodes and arthropods (6-8 other phyla)
- exoskeleton and molting
47
Arthropoda Body Plan?
- segmentation (a lot of heteronomy)
-exoskeleton (chitin)
- jointed appendages (hella diversity)
* Unity of plan, diversity of unique execution But limited size range*
48
Arthropoda Gas Exchange?
Must overcome low
permeability of the exoskeleton
- Aquatic (gills (often feathery extensions)
- Two terrestrial types (“Lungs” – localized air exchange organs (a few) or Tracheae – diffuse channels to all cells (most insects)
49
Arthropoda feeding?
- Widely variable, but adapted
to food source
- Most arthropods evolved
modified appendages for
feeding
50
Arthropoda internal transport?
- Open circulatory system
- Blood pigments (sometimes)
- Well-developed heart(s)
51
Arthropoda sensory/nervous systems?
- Highly variable, but generally
very well developed, including
Eyes - Visual receptors;
Antennae - Chemoreceptors;
“Ears” - Mechanoreceptors
52
Arthropoda movement?
- Muscles attached to
exoskeleton
- Must molt
53
Protostome summary?
* Multiple origins of effective movement (from water to land to air, use of the coelom as a hydrostatic skeleton - Annelids,
Use of a fairly rigid exoskeleton - Arthropods, Use of a muscular foot - Mollusks, especially cephalopods
* Multiple origins of segmentation
(Useful for locomotion in annelids,
Extreme heteronomy (variable segments) in arthropods)
* Separate instances of high speed and great sensory/response systems within molluscs and arthropods
54
What is the difference between Homeotic vs Homeobox Genes?
- Homeotic genes: regulate the development of anatomical structures (*not all homeotic genes have homeoboxes*)
- Homeobox genes contain DNA sequences that encode a conserved DNA-binding domain that regulates gene expression during development and differentiation (*Not all homeobox genes are homeotic! They may regulate something else*)
55
Hox genes vs MADS-box genes?
- Hox genes are homeotic and homeobox genes that regulate body parts in **animals** (in regard to AP axis)
-MADS-box genes are homeotic but not homeobox genes or HOX genes (found in plants)
56
Why is a cell being at the 16-cell embryonic stage so important when thinking about the master regulator and cell signaling?
at this stages cells will start compacting and differentiating from pluripotent cells to specialized ones. so if a cell signals before this point, ain't one thing finna happen.
57
What are the identifying traits of deuterstomes?
bilateral, segmented, and pharyngeal slits
58
Echinoderms wanted to be different so bad, so why are they different that other deuterostomes?
radial (in adults), calcified internal plates, and no pharyngeal slits
pretty much said hell naw to all the traits and prefered to be slow, reduce muscle, decephalized, reduced sense organs, and decentralized nervous system
59
Echinoderm Body Plan?
- hard calcareous endoskeleton
- Water vascular (wv) system: hydraulic canals branching to small
extensions called tube feet – movement and prey capture
WV system
60
Echinoderm Gas Exchange?
- Most across “skin”
- Some have tubular projections =“gills”
61
Echinoderm feeding?
- highly variable
- WV system are usually involved (tube feeties)
- some evert stomach
62
Echinoderm internal transportation?
- Flow distributed through elaborate
coelom via cilia
- No blood pigments
63
Echinoderm sensory/nervous?
- Highly reduced - no centralized brain
- Nerve ring connecting all 5 arms
But surprisingly sophisticated behavior
64
Echinoderm Locomotion?
- Calcareous endoskeleton
- Movement usually via tube
feet connected to water
vascular (WV) system
65
Unique chordate features?
- hollow dorsal nerve cord
- tail that goes past butt
- notochord (dorsal supporting rod)
66
Basal Chordata (Cephalochordate) traits?
- notochord
- Dorsal nerve cord
- Pharyngeal slits (Filter feeding +
Gas exchange)
67
Basal Chordata (Cephalochordate) gas exchange?
- across body surface
68
Basal Chordata (Cephalochordate) feeding?
cilia pushes water through gills and particles get stuck
69
Basal Chordata (Cephalochordate) internal transport?
-closer circulation
-no real heart (myocardial cells with tinman genes) or pigments
70
Basal Chordata (Cephalochordate) sensory/nervous system?
- little sensory specialization (primitve eyes and slight expansion for a "brain")
71
Basal Chordata (Cephalochordate) locomotion?
notochord and lateral segments of muscles work together
72
What are Tunicates = “Sea Squirts” ?
* Mobile larvae with notochord
and nerve cord
* Allows them to disperse prior
to settling into adult stage
* Filter feeders using “basket"
73
What are the 5 additional traits found in vertebrates?
1. vertebral column
2. internal skeleton supported by
vertebral column
3. Anterior skull* with large brain
4. Internal organs suspended in
coelom
5. Circulatory system with ventral
heart
*calcified bone in most but not all groups!
74
How many HOX genes clusters do vertebrates have on the 4 chromosome?
4, that may provide for more
diversity along Anterior-Posterior axis
75
Where was there a loss of HOX genes in deuterostomes?
* Many hox genes lost in tunicates
* Amphioxus (lancelets) retains them
76
Basal Vertebrates (Lampreys) gas exchange?
- Gills – gas exchange
- Muscular pharynx – moves water across gills
- Pharyngeal skeleton – ultimate source of jaws
77
Basal Vertebrates (Lampreys) feeding?
Muscular pharynx – bores holes into fish for food
78
Basal Vertebrates (Lampreys) internal transport?
- heart, pigments
79
Basal Vertebrates (Lampreys) sensory/nervous system?
brain and specialized sense organs
80
Basal Vertebrates (Lampreys) movement?
- Small vertebrae around spinal cord
- Composed of cartilage (collagen fibers) – assist notochord
81
Basal Gnathostomata (jawed vertebrates - sharks) feeding?
- jaws (hinged mouth)
- mineralized teeth
82
Basal Gnathostomata (jawed vertebrates - sharks)
83
Basal Gnathostomata (jawed vertebrates - sharks) internal transport?
closed system
84
Basal Gnathostomata (jawed vertebrates - sharks) sensory/nervous system?
enhanced vision and smell
85
Basal Gnathostomata (jawed vertebrates - sharks) movement?
2 sets of paired fins -> control
86
Bony fish feeding?
Jaws for capturing food
87
Basal Tetrapods feeding?
Suction in water, contact on land
88
Aves/Mammalia feeding?
finely grind food:
- complex teeth (mammals)
- teeth, beaks, and gizzard ( dinosaurs and birds)
89
Bony fish gas exchange
Gills for O2 capture
90
Basal Tetrapods gas exchange?
Gills, Skin and Lungs (arose a bit earlier)
91
Aves/Mammalia gas exchange
- Very large lung surface area
- More effective (but different)
means of ventilation
92
Bony fish internal transport?
single chambered heart sends
blood to gills then to body and then
back
93
Basal Tetrapods internal transport?
- Systemic and pulmonary circuits
(arose a bit earlier)
- Form a partly divided circulation
94
Aves/Mammalia internal transport?
- Fully divided circulation (2 atria, 2 ventricles)
- High blood pressure in systemic
circuit
- Lower pressure in pulmonary circuit
95
Bony fish sensory/nervous?
sophisticated
96
Basal Tetrapods sensory/nervous?
sophisticated
97
Aves/Mammalia sensory/nervous?
Still more elaborated
98
Bony fish movement?
Muscles acting on skeleton to swim
99
Basal Tetrapods movement?
Supporting limbs (evolved from
lobed fins)
100
Aves/Mammalia movement?
- Vertical posture
- Move on legs
- Though birds can use WINGS
101
Basal tetrapoda reproduction?
jelly-covered eggs (vulnerable to dry conditions) and laid in water
102
Important traits of Basal Amniota? (snakes, lizards, etc.)
* Amniotic egg (frees reproduction from water!)
* Dry scaly skin (body surface no longer important)
for gas exchange
* Other systems roughly (similar to amphibians)
103
Aves/Mammalia had independent evolution of what?
-homeothermy (constant temp and insulation)
- very HIGH metabolic rate
- Convergent form and functions
