Which of the following statements is true? Population density is number of individual organisms of a species living in a unit of area.
Water is not a limiting factor in an aquatic ecosystem.
An ecosystem can carry an unlimited number of organisms.
In a balanced ecosystem, there is no competition for resources.

Mike has a problem with his testosterone. he is unable to produce enough. which will most likely be affected by his inability to produce testosterone? check all that apply.

Fill in the blank 1. digestion occurs in the small intestine through the action of enzymes. 2. urea, excess water, and other waste materials are eliminated in a water fluid called 3. can cause infections by injecting dna or rna into hosts. 4. the human immune system produces in response to a vaccine, which later can bind to and destroy a pathogen if it invades. 5. are structures that link bone to bone at a joint 6. in the heart, blood flows from the right atrium to the right ventricle, where it is pumped to the the words i can use are: lymphocytes gliding pivot gas urine absorption dermis fulcrum lungs chemical viruses capillary vertebrae esophagus tendons antibodies synapses ligaments kidneys pathogens

The means by which a cell transports large molecules out of the cell is called