According to Paragraph 4, what is the function of the Jacobson's organ in snakes？
A. To assist in the search for chemical particles in the air.
B. To enable the tongue's fork to be spread more widely.
C. To utilize the snake's trained sense of direction.
D. To compare the sensory input of the two tongue tips.
查看答案
The word pronounced in the passage is closest in meaning to
A. controlled.
B. obvious.
C. evolved.
D. useful.
In Paragraph 2, the author states that waterwheels and windmills
A. led to the rise of Manorialism in Europe.
B. were adopted by European farmers from other peoples.
C. significantly altered agriculture in Europe.
D. were invented in the Muslim world after 1000 ＣＥ.
According to Paragraph 1, many snake species have the ability to
A. stick out their tongues while their mouths are shut.
B. imitate the behavior. of lizards.
C. bring prey into their mouths with their tongues.
D. retract the lips from their jaws.
In cross matching, how does a compatible match appear under the microscope？
All of the cells are at an equal distance from each other.
B. The arrangement of the cells looks like two parallel lines.
C. The cells tend to group together in a large clump.
D. The red cells and the plasma separate in an irregular pattern.
微信支付 
支付宝支付