The amphibian also develops a system and a three chambered heart.
a. nervous
b. skeletal
c. circulatory
d. digestive

How many trophic levels are there in the following food chain? phytoplankton - shrimp - perch - pike - osprey

How is the male reproductive system different from other body systems? it isn’t necessary to vital signs. it monitors other body systems, and adjusts if necessary. it transports items from one system to another. it is the only system that produces hormones in the male.

Ihave no idea how to solve these. plus there's another question that is 2) a 10 kilogram meteorite is collected in space and brought back to earth. it is composed of 1.25 kg of uranium-238 and 8.75 kg of lead-206. how many u-238 half lives have passed? what is the approximate age of the meteorite?