Which of the following examples of an ecological study involves the ecosystem level of organization? 1. effects of competition on survival 2. effects of an invasive plant species on birds nesting sites 3. effects of a disease on population size 4. the effects of human activities on biogeochemical cycling

The image shows ekgs of a person with normal heart waves and of a person having tachycardia. based on this image, what kind of condition is tachycardia? a. the heart beats abnormally fast. b. the heart beats abnormally slow. c. the right atrium of the heart stops working. d. the left ventricle pumps less blood to the aorta.

Ais a landform that is formed at the mouth of a river from the deposition of sediment carried by the river as the water flows.

Acertain species of fish can have either long or short fins. the allele for long fins is dominant over the allele for short fins. a heterozygous, long-finned fish is crossed with a homozygous, short-finned fish. of the offspring, will have long fins and be , and will have short fins and be .