Question

5.4 is the plane of division during fission along the longitudinal or the transverse axis?
5.5 why is conjugation considered a form of sexual reproduction?
5.6 what evolutionary benefit does conjugation provide that fission does not?
vorticella
next you will examine vorticella, a sessile, stalked ciliate commonly found in stagnant bodies of freshwater. vorticella typically remains attached to aquatic vegetation by a contractile stalk and possesses a funnel - shaped cell body with a ring of cilia around the larger peristome (open end). a contractile body permits vorticella to push its cell body farther away from both the substrate and neighboring individuals to compete for food. the cilia beat rapidly to create currents that pull food particles into the peristome, where they are channeled to the buccal cavity for digestion.
procedure
1 prepare a wet mount from a culture of living vorticella, add a coverslip, and examine under medium or high power (fig. 6.12).
2 closing the iris diaphragm and adjusting the condenser on your microscope to increase image contrast usually improves observation of these small, transparent organisms.
do the cilia surrounding the peristome of vorticella beat in random fashion or in coordinated waves?
3 while viewing a specimen that is fully extended through the microscope, have your lab partner tap once or twice gently on the coverslip with a dissecting needle and describe the organisms response.

Explanation:

5.4: In Vorticella, fission occurs along the transverse axis.
5.5: Conjugation is sexual reproduction as it involves genetic material exchange between two individuals.
5.6: Conjugation allows for genetic recombination, introducing genetic diversity which can be an evolutionary advantage over asexual fission. For the cilia - they beat in coordinated waves to create currents for feeding. When the coverslip is tapped, the Vorticella may contract its stalk due to the contractile body to move away from the disturbance.

Answer:

5.4: Transverse axis
5.5: Involves genetic material exchange between two individuals
5.6: Introduces genetic diversity through genetic recombination
Cilia: Beat in coordinated waves
Response to tapping: May contract its stalk due to the contractile body