DFF Lab Quiz 2
Deuterostomes after becoming fertilized:
-Cleavage -change in form often beings with gastrulation, involves cell movement -emergence of pattern -differentiation of cells -growth
Our experiment: Anitbody detecting ELISA
-Start with known antigen in all tests -is there an antibody in the sample that can bind to the antigen? -How do we determine if that binding occurred? -Enzyme-linked secondary antibody -addition of substrate detects presence of 2^o Ab+Enzyme
Features that vary in invertebrate phyla: Body systems:
-What body systems are present? -How does an animal survive without a given system (ex: without a circulatory system)?
All vertebrate animals dissected include the following features:
-anterior skull with a large brain -a rigid internal skeleton supported by the vertebral column -dorsal hollow nerve cord -well-developed circulatory system driven by contractions of a ventral heart.
Features that vary in invertebrate phyla: Tissue layers:
-are there distinct tissue layers? -how many are there in development? (not the same as how many tissue types!)
Invertebrate animal characteristics to examine
-body plan -food acquisition -locomotion -organ systems
ELISAs (Enzyme-Linked ImmunoSorbent Assay):
-can be set up to detect either an antigen or an antibody in a sample -both types of test rely on specific antigen-antibody binding -differ in order of reagents added
All vertebrates have:
-circulatory systems -digestive systems -gas exchange systems How do they differ/how have they evolved over time
Connective tissue
-consists of a sparse collection of cells scattered through an extracellular matrix (fibers embedded in fluid, gel, or solid foundation) -Function: connection of body tissues, structural framework for the body; protection of internal organs; energy storage Ex: cartilage, bone, adipose, blood 2 types: loose, fibrous
Fertilization What events occur after sperm and egg plasma membrane contact, but before first cleavage?
-fast block to polyspermy -calcium wave -Na-H exchange -slow block to polyspermy -pH changes -DNA protein synthesis activated -nuclear fusion -spindle formation
Epithelial tissue
-form sheets of densely packed and tightly connected cells that cover inner and outer body surfaces -functions: body protection, absorption, secretion, filtration, and transport; some are modified to detect chemicals
How do vertebrate systems differ/how have they evolved over time?
-jaws, teeth, paired fins evolved in sharks -bony skeleton, swim bladder/lung evolved in fish -lobe fins evolved for amphibians -terrestrial limbs and digits evolved for amphibians amniotic egg evolved for birds/reptiles
Antibodies
-produced by the immune system to inactive the foreign antigen
Muscle:
-specialized for contraction (shortening) -functions: rhythmic, involuntary contraction of hollow organs; voluntary movement of parts of the body such as long appendages and jaws Types: skeletal, smooth, cardiac
Nervous Tissue
-specialized to generate, send and receive electrochemical signals -functions: communication between different regions of the body; controlled, coordinated activity of the body; repeatable responses to external stimuli ex: neurons, neuroglia
Invertebrate animals to be dissected:
-sponge -comb jelly -hydra (live) -anemone -planaria (live) -earthworm -clam -roundworm (Ascaris) -crayfish -grasshopper -starfish -lancelet
Elisa uses: antibody detection
-virus testing by assaying for Ig molecules specific to viral antigens -Use known antigen to capture antibody, of present, in a sample
Sea Urchin Outcomes Regular seawater no sperm no chemical
1% fertilization envelope 1% first cleavage 167 observed
Sea Urchin Outcomes calcium free seawater no sperm no chemical
1% fertilization envelope <1% first cleavage 101 observed
Sea Urchin Outcomes low sodium seawater no sperm no chemical
1% fertilization envelope <1% first cleavage 81 observed
Features that vary in invertebrate phyla:
Tissue layers Symmetry body cavity body systems segmentation
Frog egg contains more yolk in the _____________ and affects __________.
Vegetal pole; cleavage
The evolution of segments: Segmentation:
Williston's Law (applied to phyla that have segmentation) - over time, segments tend to...... -reduce in total number -specialize function of remaining segments
Calcium wave triggers:
activation of sodium-proton pump exchange. protons are pumped out of the cell , pH starts to rise and then DNA/protein synthesis are activated.
Frog model Site of sperm entry
animal pole
Hormones:
are reseased from glands and travel through the blood stream, sometimes over long distances, to target organs.
NH3Cl is
base (to increase pH)
Removing free calcium by chelating agent (EGTA) _________ later steps.
blocks; (calcium rise is necessary)
EGTA is
calcium chelator (sequesters calcium out of solution)
A23187 is
calcium ionophore (which allows calcium to equilibrate over plasma membrane. calcium stores are in endoplasmic reticulum)
Features that vary in invertebrate phyla: Segmentation
can be obvious externally or internally
Vertebrates are a subgroup of ____________.
chordates
proximal
closer to the body or trunk
Holoblastic cleavage
complete ex: frog
ELISA this test is somewhat sensitive to the ______________ of the primary antibody.
concentration
Meroblastic cleavage
incomplete ex: fish
involution
individual cells moving inward (mesoderm, endoderm)
Calcium increase occurs even in calcium free water, so source of calcium must be ___________.
internal (from endoplasmic reticulum)
types of movements that occur during gastrulation:
invagination involution epiboly
Features that vary in invertebrate phyla: Body cavity:
is there a body cavity (lined with epithelium or not?) that contains digestive tract and other organs?
Fast block to polyspermy
membrane depolarization
Frog is cleavage always completed before the next cleavage starts?
no
In sodium free seawater, protons ________ pumped out and pH _________ rise. Protein synthesis _________ activated.
not; doesn't; isn't (pH rise is necessary)
A tube comprised of mesoderm, the ____________, is formed in the embryo.
notochord
ELISA Experimental Controls using positive and negative controls What reagent is purposely being included/left out of these samples:
primary antibody
Features that vary in invertebrate phyla: Symmetry:
radial vs bilateral
Adding NH3Cl with no sperm can ________ the egg pH and _________ protein synthesis
raise; activate (increase pH is sufficient)
slow block to polyspermy
release of cortical granules after Ca2+ "explosion"
pH rise and not __________ inflow is necessary and sufficient for protein synthesis activation.
sodium
Invagination
tissue of connected cells buckle inward due to changes in cell shape: endoderm
dorsal
toward the back (spine)
ventral
toward the belly
Anterior (cranial)
toward the head
medial (median)
toward the middle
posterior (caudal)
toward the rear
lateral
toward the side or away from midline
Frog The presence and distribution of what substance explains particular patters of cleavage in the frog?
yolk (controls how much cleavage because cleavage generally occurs in the animal pole where there is no yolk)
Multi-cellular heterotrophs
All animals, by definition are this. use internal processes to breakdown food from their environment.
ELISA no color change =
No enzyme present, no secondary antibody present, no primary antibody present in the suspect sample
what type of cleavage occurs in the frog?
holoblastic
A major regulator of the endocrine system in mammals is the ______________, a region of the brain.
hypothalamus
How our ELISA works:
1. add antigen to wells, wash 2. add sample which may contain antigen-specific primary antibody, wash 3. add secondary antibody, which is linked to an indicator enzyme, wash VERY WELL 4. add substrate and watch for color indicator appear
Sea Urchin Outcomes low sodium seawater no sperm chemical: A23187
17% fertilization 4% first cleavage 77 observed
Sea Urchin Outcomes calcium free seawater yes sperm Chemical: EGTA
19% fertilization envelope 6% first cleavage 87 observed
Sea Urchin Outcomes regular seawater yes sperm chemical: NH3Cl and EGTA
20% fertilization envelope 7% first cleavage 65 observed
Sea Urchin Outcomes calcium free seawater no sperm Chemical: A23187
23% fertilization envelope 4% first cleavage 101 observed
Sea Urchin Outcomes low sodium seawater yes sperm chemical: NH3Cl
24% fertilization envelope 11% first cleavage 79 observed
Sea Urchin Outcomes regular seawater yes sperm Chemical: EGTA
25% fertilization envelope 11% first cleavage 100 observed
Sea Urchin Outcomes Low sodium seawater yes sperm no chemical
26% fertilization envelope 8% first cleavage 165 observed
Sea Urchin Outcomes regular seawater no sperm chemical: A23187 and EGTA
31% fertilization envelope 4% first cleavage 87 observed
Sea Urchin Outcomes regular seawater no sperm chemical: A23187 and NH3Cl
35% fertilization envelope 5 % first cleavage 42 observed
Sea Urchin Outcomes regular seawater no sperm chemical: A23187
40% fertilization envelope 8% first cleavage 185 observed
Sea Urchin Outcomes calcium free seawater yes sperm no chemical
41% fertilization envelope 20% first cleavage 184 observed
Sea Urchin Outcomes regular seawater yes sperm chemical: NH3Cl
42% fertilization envelope 19% first cleavage 69 observed
Sea Urchin Outcomes regular seawater yes sperm no chemical
62% fertilization envelope 34% first cleavage 368 observed
Fertilization Effect of varying concentrations of chemicals in the seawater in the presence or absence of sperm:
Ca2+, Na+, A23187, EGTA, NH3Cl
Bastula undergoes gastrulation to form 3 germ layers:
ectoderm, endoderm, mesoderm
The ______________ system utilizes chemical messangers called _________
endocrine; hormones
ELISA color change to blue
enzyme was present secondary antibody was present primary antibody was present in the suspect sample
ELISA The secondary antibody has bound to it an ______________ (HRP, horseradish peroxidase) that will catalyze the reaction that turns substrate (TMB, tetremethylbenzidene) from __________ to ________.
enzyme; colorless; blue
distal
farther away from the body or trunk
Antigens
foreign particles (often proteins) that elicit an immune response
Artifical release of calcium by calcium transporter (A23187) can trigger similar downstream affects as __________.
sperm; (calcium rise is sufficient)
Epiboly
stretching and rearrangement of multiple layers of tissue into fewer layers over the surface of the embryo.
ELISA The secondary antibody will bind to
the primary antibody
The grey crescent is created by:
the rotation of the cortical cytoplasm relative to the inner cytoplasm.
Cleavage:
the special mitoses which begin immediately after fertilization