Population Density_Symbiosis

Ostriches and gazelles eat together.  They both watch for predators and danger.  Since they see things differently, they each can identify threats the other animal may not see.  Both species are benefited.  

• mutualism
• commensalism
• predation
• parasitism

Yucca flowers are pollinated by yucca moths.  The moths lay their eggs in the flowers and the eggs hatch. The larvae eat some of the seeds, and  spread them around.  Both species are benefited.

• mutualism
• commensalism
• parasitism
• competition

Mistletoe takes water and nutrients from the oak tree. This is good for the mistletoe but bad for the tree.

• mutualism
• commensalism
• parasitism
• competition

Hermit crabs live in shells made and then abandoned by snails. This neither harms nor benefits the snails.

• commensalism
• parasitism
• mutualism

Hookworms enter the human body by burrowing into the skin of the feet. Once in the skin they enter the bloodstream and travel to the small intestine where they attach to the walls and begin to drink the person's blood and weaken the victim.

• parasitism
• mutualism
• commensalim

A win-win relationship

• Commensalism

• Parasitism

• Predation

• Mutualism

A win-lose relationship.

• Mutualism

• Commensalism

• Competition

• Parasitism

The close relationship between two different species in an ecosystem

• Biosphere

• Ecology

• Symbiosis

• Environment

When a mosquito bites you, you are the __________ and the mosquito is the  ____________.

• host, hostess
• parasite, host
• host, parasite
• prey, predator

A frog eats a fly. The frog and fly are demonstrating ________.

• mutualism

• competition

• predator/prey

• parasitism