A trachae system for bringing air into the body would only be associated with which of the following circulation systems?

 In order to efficiently exchange gases the respiratory membrane must be:

 In which group of animals does blood flow from the respiratory organ to the heart before circulating to the rest of the body

 ____ muscle controls an animals width and ___ controls its length

 Separation of the circulation into a pulmonary (to the lungs) and systemic (to the organs)  portion has what implications?

To answer this question, access the CSIRO Invertebrate Dichotomous Key (CLICK HERE TO ACCESS).

During fieldwork for a biodiversity survey, you come across an invertebrate specimen you wish to identify. The specimen was long and had clear antennae, but upon being picked up formed the arrangement seen in the image below:

Using the key, how would you class this specimen?

In order to increase efficiency, birds have a ___ cycle ventilation system and make use of ____ current airflow

 An animal experiences hard shocks as it jumps while chasing its prey, in order to protect its organs while doing this it would be a;

Fill in the blanks: 

The embryo of a cnidaria has ___ germ layers while bilaterians have ____.