Their incomplete digestive system is composed of a cavity with a single opening for the entry and exit of food and waste, respectively. ... They sense their environments by a rudimentary nervous system composed of a nerve net. ... They possess a complete digestive system as well as a closed circulatory system. Their nervous system is made of a brain and a nerve cord. ...

• Word Count: 377
• Approx Pages: 2

Myths, symbols and cultures are attached with a term spider. The words serenity, persistence, mischief, revulsion, fear, disgust, indebtedness, and curiosity are associated with arachnids. Spiders influence all sort of art e.g., Literature, Music and Movies etc. The associations with spider are from...

• Word Count: 646
• Approx Pages: 3
• Grade Level: High School

The DNA of human blood can be recovered from the digestive tract of an insect that has feed on an individual. ... The two dark spots on the left are the posterior spiracles, or openings to the breathing system. ...

• Word Count: 2073
• Approx Pages: 8
• Grade Level: High School

The DNA of human blood can be recovered from the digestive tract of an insect that has feed on an individual. ... The two dark spots on the left are the posterior spiracles, or openings to the breathing system. ...

• Word Count: 2083
• Approx Pages: 8
• Grade Level: High School