Answer:
A.)are ectothermic organisms with variable body temperatures.
Explanation:
Invertebrates animal are animals that lack a backbone, Land invertebrates include insects,spiders, centipedes ,coelenterate, an arthropod, mollusc and the rest.
Ectotherms are also called called cold-blooded animal because their bl body temperature regulation is dependendent on external sources, such as sunlight or a heated rock surface. Some of the examples of ectotherms are fishes, amphibians, invertebratesand reptiles. The aquatic ectotherms body temperature is usually compare closely to the temperature of the surrounding water
Ectothermic species that lives in temperate regions usually experience rapid and potentially stressful changes in body temperature simply because of weather changes even among amphibians there is variation in their temperature
It is believed that naturally occurring periods of temperature variation negatively impact amphibian health.
9:3: 3:1 is the phenotypic ratio showing traits as black and long hair : black and short hair: chestnut and long hair: chestnut and short hair when a chestnut horse heterozygous for pacing and hair length with a hybrid horse.
Explanation:
Dominant trait = black hair colour (BB,Bb), trotting (TT,Tt) , long hair (LL,Ll)
recessive trait = chesnut hair colour (bb), pacing gait (tt), short hair(ll)
cross between chestnut horse heterozygous for pacing and hair length will have alleles as BbLl
alleles for hybrid horse will also be heterozygous Bb, Ll
Punnett square to show the cross:
BL Bl bL bl
BL BBLL BBLl BbLL BbLl
Bl BBLl BBll BbLl Bbll
bL BbLL BbLl bbLL bbLl
bl BbLl Bbll bblL bbll
phenotype ratio
black and long hair : black and short hair: chestnut and long hair: chestnut and short hair
9:3: 3:1 is the phenotype ratio.
(A) A large amount of nitrates in the water :)
The first step the biologist needs to make an observation in which to create a hypothesis.
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