Are bones made of cartilage and ligaments

Why zebra fish experience similar genetic disease as human

1. beginning with all chambers of the heart in the "relaxed" phase, describe the cardiac cycle in mammals, with systole and diastole of the atria and ventricles. for each time point in the cycle you select, state the following: • whether the atria and ventricles are contracting or relaxing • whether the av valves and semilunar valves are closed or open • whether the pressure in the atria and ventricles is high or low

Why does competiton happen? a: different organisms have different needsb: there are limited resources in an ecosystemc: there are no predators in an ecosystemd: organisms do not need the same resources (i think it's b but i'm not sure)