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.
Explanation:
the first one and the last one is transverse
It is b . Because three of them are less than 90.
Your wording is a bit confusing, but I get what you're trying to say.
Here's what the life cycle of a star looks like.
Stars begin as giant balls of hydrogen colliding together and releasing a ton of energy. This hydrogen will eventually fuse together to form helium, and once all of the hydrogen has become helium, This helium will, after a very long time and under lots and lots of pressure, form carbon. When this happens, it is considered a red giant, and the star becomes bigger and less bright. The star will become less and less bright and eventually start to shrink as all of that carbon turns to heavier elements like iron, turning into a dwarf star that eventually dies out.
(Dwarf stars are still shining are called white dwarf stars, and dead ones are black)
The cool part, though, is that massive stars (those which have a mass of at least 3 times the Sun's) turn into heavy elements so fast that the core collapses almost instantaneously and explodes violently into a ball of fire known as a supernova.
Sometimes the core of the star gets left behind, and either forms a neutron star or, if it has the mass of a massive star, will collapse in on itself and become a black hole.
Take for example - you touching something sharp and instantly moving your hand away.
Sensory neurons in your fingers detect the external stimuli of the sharp object and send a nerve impulse to the spinal cord (does not reach brain) and is sent back to a motor neurone - attached to an effector that moves the muscle and moves the hand away. This is a rapid reflex action and involuntary.
