1. Bell Ringer #3 Jan 30/31

2. Question 1  Dogs (Canis familiaris) are most closely related genetically to which of the following organisms?  A African hunting dog (Lycaon pictus)  B Gray wolf (Canis lupus)  C Grizzly bear (Ursus arctos)  D Domestic cat (Felis catus

3. Question 2  The medulla, part of the brain stem, reacts quickly to increased levels of CO 2 in the blood and stimulates a response from the —  A excretory system  B immune system  C respiratory system  D integumentary system

4. Question #3 Lactose is a naturally occurring sugar found in milk. Some dairy products, such as yogurt, may contain live bacteria. These products are useful to people who lack the ability to digest lactose. What does this information demonstrate? A Bacteria raise the acidity of processed foods. B Some bacteria interfere with digestion. C Bacteria can prevent insulin production. D Some bacteria are beneficial to human health.