Usually they can show these emotions, too. Mammals nourish their offspring with love just like we do. Many animals mourn their dead mates and family members, too. These things give life value. Plants don't have these things.
Most animals can also show that they hurt or suffer when their basic needs are denied.
It is this suffering that is our best reason for valuing the quality of life for animals in our care. Again, plants cannot suffer, they have no nervous system nor consciousness to understand suffering. This is why it is generally acceptable to eat plants, but not animals. You agree to defend, indemnify, and hold harmless Animal Rights in Action, its officers, directors, employees, agents, volunteers and third parties, from your use of this service.