Questions With Complete Solutions
1st and 2nd pair of pleopods in males are Correct Answers
gonopods - sperm transfer
3 key points of Metamorphogenesis Correct Answers 1) loss of
cells/tissues
2) De novo differentiation of cells/tissues
3) Remodelling of larval cells/tissues
Absorptive cells are Correct Answers modified protonephridial
duct cells
Accommodations for spermcast mating Correct Answers - long
lasting sperm
- Female ability to sequester sperm
acrosome reaction in sea urchins Correct Answers -initiated by
interaction with specific egg jelly carbohydrates
-egg jelly carbohydrates bind to receptors on sperm membrane
above acrosomal vesicle
-binding of carbohydrate in jelly layer opens calcium channels
and calcium enters sperm head (causes fusion of acrosomal
membrane with sperm cell membrane)
-exocytosis of the acrosomal vesicle
-release of enzyme digest outer layer of egg
-protrusion of acrosomal process occurs by polymerization of
globular actin into filaments due to calcium influx
-protrusion puts Bindin on exterior of acrosomal process and
this leads to egg binding to sperm
,Adult sand dollars exclude tanaids by Correct Answers
disrupting their tubes
After tubercles were filed off there was a Correct Answers
reduction in critical size and increase in predation success
Aglantha Giant axons Correct Answers - giant axons carry two
different signals that generate different behaviours
- Fishing (slow swim) is mediated by Ca 2+ channels of giant
axons
-escape jetting mediatd by Na+ channels of giant axons
Allomones Correct Answers - producer and receiver are
different species
Benefits producer
Anti predator mechanisms in 3 morphological types of lobsters
OFFENSE Vs. DEFENSE Correct Answers - lobsters tethered
to iron stakes
- 40 experiments for each species 20 intact + 20 manipulated
- checked at 4 hours and at 24 hours
conclusion the amount of predation suffered by the 3 species of
lobsters was best explained by the strength of their respective
carapaces not by the weaponry they possessed
Antifouling experiments Correct Answers trirerpene glycosides
were shown to inhibit settlement of larvae in a 20-30d field
experiment.
,Used control and treated petri dishes
Any deformable, incompressible material maintained at constant
volume Correct Answers can act as a hydrostatic skeleton
Aplysia Californica (sea slug) Correct Answers - secrete from
ink gland and opaline gland when disturbed for defence
aposematic colouration Correct Answers Bright and
conspicuous colouration displayed by many toxic or distasteful
potential prey species
Associative S&M Correct Answers Environmental induction
cue (chemical factor) comes from an organism of a different
species
post metamorphic prey (presence of prey induces
metamorphosis)
good habitat indicator (algae is present in abalone)
Avoidance S&M Correct Answers Environmental cue inhibits
metamorphosis
- Superior competitor during benthic stage
- Predator of benthic stage?
Bag cells Correct Answers are neurosecretory cells that secrete
egg laying hormone
, Batesian mimicry Correct Answers - edible animal resembles a
noxious animal
Benefits of pelagic lifestyle experiment> Correct Answers
percent loss per minute of tethered megalopae of C. magister
results showed benthic deployments were preyed upon more
Bindin Correct Answers - gamete recognition protein of sea
urchins
-exposed on acrosomal process by acrosome reaction
- Bindin receptors on vitelline envelope of the egg
-facilitate conspecific gamete binding
Bindin function Correct Answers After acrosome reaction,
bindin within acrosomal process
- Bindnin binds to receptors on vitelline envelope
Bioluminescence Correct Answers a chemical reaction within a
organism that emits light
bioluminescence for defence Correct Answers Counter-
illumination:
Hides silhouette when viewed from below
Misdirection - smoke screen
Biominerals are composite materials consisting of Correct
Answers mineral and organic component