1.
A lichen is a combination of fungus and algae that lives on the sides of trees, rocks, and other materials. The fungus provides the algae with water and minerals, and the algae use the water and minerals to make food for both organisms. What type of relationship does the lichen represent?
Correct Answer
C. Mutualism
Explanation
The relationship between the fungus and algae in a lichen is mutualism. In mutualism, both organisms benefit from the relationship. The fungus provides the algae with water and minerals, which the algae use to produce food through photosynthesis. In return, the algae provide the fungus with food in the form of carbohydrates. Both organisms rely on each other for survival and benefit from the partnership.
2.
Which of the following is an example of mutualism, a type of symbiotic relationship?
Correct Answer
B. An orchid growing on the branch of a tree.
Explanation
Mutualism is a type of symbiotic relationship where both organisms involved benefit from the interaction. In the case of an orchid growing on the branch of a tree, the orchid benefits by obtaining support and access to sunlight, while the tree may benefit from the orchid's ability to attract pollinators or provide nutrients. This interaction demonstrates mutual benefit for both organisms involved.
3.
When a symbiotic relationship benefits both organisms, it is an example of:
Correct Answer
B. Mutualism
Explanation
When a symbiotic relationship benefits both organisms, it is an example of mutualism. In mutualism, both organisms involved in the relationship receive benefits, leading to a mutually advantageous situation. This type of symbiotic relationship is characterized by cooperation and interdependence, where both organisms rely on each other for survival and reproduction. The interaction between the organisms is mutually beneficial, enhancing the fitness and success of both parties involved.
4.
How does a crocodile benefit from a bird eating from its mouth?
Correct Answer
A. It gets its teeth cleaned.
Explanation
Crocodiles benefit from a bird eating from its mouth because it helps to clean their teeth. The bird acts as a natural toothbrush, removing food particles and debris that may be stuck between the crocodile's teeth. This cleaning action helps to maintain the crocodile's dental hygiene and prevent dental issues such as tooth decay or infections.
5.
How do people benefit from bacteria in their intestines?
Correct Answer
B. Gut bacteria help break down food components.
Explanation
Gut bacteria play a crucial role in breaking down food components that the human digestive system struggles to process independently. This includes certain fibers and carbohydrates, which are resistant to digestion by human enzymes. Gut bacteria possess specialized enzymes capable of breaking down these complex compounds into simpler forms that can be absorbed and utilized by the body for energy and other essential functions.
6.
When a symbiotic relationship helps one organism and hurts the other, it is an example of:
Correct Answer
C. Parasitism
Explanation
Parasitism is the correct answer because it refers to a symbiotic relationship in which one organism benefits while the other is harmed. In parasitism, the organism that benefits is called the parasite, and it relies on the host organism for its survival and reproduction. The host organism, on the other hand, experiences negative effects such as reduced fitness or damage to its tissues. This type of relationship is common in nature, with examples including fleas on dogs, ticks on humans, and tapeworms in the intestines of animals.
7.
The harmed species in a parasitic relationship is called:
Correct Answer
C. The host
Explanation
In a parasitic relationship, one species benefits at the expense of another. The species that is harmed and exploited by the parasite is known as the host. The host provides resources and a suitable environment for the parasite to thrive and reproduce, often causing harm or damage to the host in the process. Therefore, the correct answer is "the host."
8.
The following picture is an example of what kind of symbiotic relationship?
Correct Answer
C. Parasitism
Explanation
The picture provided shows an example of parasitism. In parasitism, one organism benefits (the parasite) while the other is harmed (the host). Based on the image, it can be inferred that the organism in the picture is benefiting from the host organism, which indicates a parasitic relationship.
9.
The following pictures are an example of what kind of symbiotic relationship?
Correct Answer
A. Commensalism
Explanation
The pictures are an example of commensalism because one organism benefits while the other is neither harmed nor benefited. In commensalism, one organism benefits from the relationship while the other organism is unaffected.
10.
Leeches have been used for medicinal purposes. The leech benefits by getting blood (food) from humans. How do humans benefit from the mutualistic relationship?
Correct Answer
A. The leech helps improve blood flow in the human
Explanation
In this mutualistic relationship, humans benefit from the leech by improving blood flow. Leeches secrete a natural anticoagulant called hirudin, which prevents blood from clotting. This allows the leech to feed on the blood for a longer period of time. However, this also has a positive effect on the human host, as improved blood flow can help to alleviate conditions such as congested veins or blood clots. Therefore, the leech's presence helps to improve blood circulation in the human, making it the correct answer.