An example of a xerophyte would be moss a cactus corn hornwort

cactus

A xerophytic plant is a species of plant that exhibit adaptations which allows them to survive in an environment where the atmosphere is dry and water availability is low. The regions where the xerophytic plants grow are deserts, ice or snow covered regions such as Artic or Alps.  

An example of a xerophyte would be cactus. Cactus are the xerophtic plants which dominate deserts as vegetation. These are leafless spiny plants, to prevent the loss of moisture by transpiration, the stems of these plants are called as succulent as they are adapted to store water.  

b tumor cells have a cell wall instead of a membrane

explanation:

tumor cells different from normal cells because tumor cells have a cell wall instead of a membrane.