Question

1. what is the approximate human population?

a. 8 million
b. 100 million
c. 8 billion
d. 100 billion

1. one way humans can combat the effects of climate change is to

a. cut down more trees
b. drive less and use public transportation
c. use more electricity
d. use more chemicals on crops

1. which of the following explains commensalism?

a. clownfish seeks protection from the stinging tentacles of sea anemones. it also protects the sea anemone from other fish that eat them.
b. orchids grow on the top of branches of trees to reach sunlight and collect rainwater. it does not rob the tree of nutrients nor is the tree affected.
c. bats feed on fruit trees and scatter their seeds through their droppings.
d. the dog can host a variety of parasites, including fleas, ticks, and heartworms.

Explanation:

Question 5

Step1: Recall human population data

The approximate human population as of recent estimates is around 8 billion.

Step2: Match with options

Option c is "8 billion", which matches the approximate human population.

Step1: Analyze each option

• Option a: Cutting down more trees increases carbon dioxide and worsens climate change.
• Option b: Driving less and using public transport reduces fossil fuel use, lowering greenhouse gas emissions, which combats climate change.
• Option c: Using more electricity (if from non - renewable sources) increases emissions.
• Option d: Using more chemicals on crops can harm the environment and not directly combat climate change.

Step2: Identify the correct option

Option b is a valid way to combat climate change.

Step1: Recall commensalism definition

Commensalism is a relationship where one organism benefits and the other is neither helped nor harmed.

Step2: Analyze each option

• Option a: Clownfish and sea anemone have a mutualistic relationship (both benefit).
• Option b: Orchids growing on trees: the orchid benefits (gets sunlight/rainwater), the tree is not affected. This is commensalism.
• Option c: Bats and fruit trees: bats get food, trees get seed dispersal (mutualism).
• Option d: Dog and parasites: parasites benefit, dog is harmed (parasitism).

Step3: Identify the correct option

Option b shows commensalism.

Answer:

c. 8 billion

Question 6