Witch best defines matter?

Aperson with age is more likely to catch diseases that healthy people usually don’t catch.what are these infections called?

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

Answer asap 50 points which of the following distinguishes the soil composition of grassland? 1. the soil supports large trees with thick, long roots, so horizon b needs to be deep enough to sustain larger flora. 2. the soil supports large trees with thick, long roots, so horizon a needs to be deep enough to sustain larger flora. 3. the soil supports small plants and shrubs with short roots, so horizon a needs to be deep enough to sustain smaller flora. 4. the soil supports small plants and shrubs with short roots, so horizon b needs to be deep enough to sustain smaller flora.