Life Science
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4th Grade Science › Life Science
Plants do not have structures that aid in their survival.
True
False
Explanation
This statement is false. Plants have many structures that are suited for survival. Leaves, roots, flowers, petals, stems, and seeds are all examples of a structure that a plant has that keeps it alive. Each feature plays a specific part in the plant's survival. Plants have adapted to their surroundings to have the best opportunity at life.
When a habit has limited resources, there is a struggle between organisms within the habit to survive. What can this be described as?
Competition
Predation
Prey
Predator
Explanation
In order to answer this question correctly, we need to understand the terms in the answer choices.
Predation is when an organism hunts and kills another organism to eat.
Prey: Within the process of predation, the prey is the organism that gets killed.
Predator: Within the process of predation, the predator is the organism that does the killing.
Competition is when a habit has limited resources and there is a struggle between organisms within the habit to survive
The correct answer for this question is competition.
Platypus have a "sixth-sense" that allows them to hunt underwater: electroreception. To find meals in the mud, it uses its bill to detect movements and subtle electric fields produced by its prey. Receptors on the bill detect changes in pressure and motion. Two types of receptors track the electrical signals produced by small prey when they contract their muscles. The platypus moves its head side-to-side to determine the direction and distance of its next meal by collecting and processing this sensory information. The platypus has about 40,000 of these special receptors.
Based on the passage, which of the following sentences best describes how the platypus processes an electrical signal?
The platypus’ tail first detects the signal and works as an oar to turn it in the right direction.
The platypus’ eyes see the movement of the electrical signal, which is then processed by its brain.
The platypus cannot process electrical signals because it is a platypus.
The platypus’ bill detects the movement of the electrical signal, which is then processed by its brain.
Explanation
The passage explains that platypus use electroreception signals via their bills to locate prey. Their bill may first detect the signal, but their brains must process the signal to then begin their hunt. Remember that the brain processes all information received from the senses.
Andy says that animals have structures that help them survive, but the skin is not one of those structures. Which of the following arguments DISPROVES Andy’s statement?
Armadillos, hedgehogs, and porcupines all have armor-like skin, which protects them from predators and harsh environments.
Arthropods have exoskeletons that they molt as their bodies grow.
Mollusks, like snails, have calcified shells that protect them from predators and rough seas.
None of these arguments disprove Andy’s statement.
Explanation
Andy is arguing that skin cannot help an animal survive, but he can be proven wrong. Many mammals, such as armadillos, hedgehogs, and porcupines, have protective skin features, such as quills and bony plates. These features of skin not only protect the animals from predators but also harsh habitats.
Which structure(s) on a rattlesnake help it to survive?
Tongue for taking in sensory information
Scales for camouflage
Rattle for warning predators
All of the answer choices are correct
Explanation
The rattlesnake pictured has all three of the structures listed for survival and more! Snakes use their tongues as a way to "taste" or "touch" the air to receive sensory information; they have colored scales that can act as a warning to other predators or even as camouflage in their habitat. Rattlesnakes are unique in that they have a rattle on the ends of their chair that they can shake and vibrate as a warning to predators to stay away. These structures help snakes to survive in challenging places.
Some plants have fibrous roots that branch in many different directions. These roots help the plants to absorb water quickly, while also holding them in the ground. In which of the following scenarios would fibrous roots serve as a structure for a plant’s survival?
A forest fire overtakes a large area of land
A hurricane ravages a beachfront
A storm causes a river to crest and flood the surrounding area
A bolt of lightning strikes a tall tree
Explanation
Because fibrous roots can help hold a plant in the ground, in the event of flooding, this root system would help anchor the plant in place, thus allowing it to survive. While these types of roots do enable plants to absorb water, this ability alone would not cause the plant to survive an event such as a forest fire, lightning strike, or hurricane.
Which of the following is NOT an example of a feature an animal may use to receive information about its surroundings?
Whiskers
Ears
Sight
Stomach
Explanation
Animals have many different features that they use to receive information about their surroundings. For example, a cat can use its whiskers to determine whether its body would fit through a tight space. Moths use their sense of hearing to avoid being hunted by bats. Birds of prey have long-distance sight to be able to spot prey from far away.
The brain is where all information received from the senses is processed.
True
False
Explanation
Animals take in information through their five senses, just like humans. Once the information is received, it is processed for understanding and reaction. The brain is the hub for all processing. The mind will send out messages to the rest of the body with instructions on how to react or behave with the information the five senses collected.
The brain is where all information received from the senses is processed.
True
False
Explanation
Animals take in information through their five senses, just like humans. Once the information is received, it is processed for understanding and reaction. The brain is the hub for all processing. The mind will send out messages to the rest of the body with instructions on how to react or behave with the information the five senses collected.
Platypus have a "sixth-sense" that allows them to hunt underwater: electroreception. To find meals in the mud, it uses its bill to detect movements and subtle electric fields produced by its prey. Receptors on the bill detect changes in pressure and motion. Two types of receptors track the electrical signals produced by small prey when they contract their muscles. The platypus moves its head side-to-side to determine the direction and distance of its next meal by collecting and processing this sensory information. The platypus has about 40,000 of these special receptors.
Based on the passage, which of the following sentences best describes how the platypus processes an electrical signal?
The platypus’ tail first detects the signal and works as an oar to turn it in the right direction.
The platypus’ eyes see the movement of the electrical signal, which is then processed by its brain.
The platypus cannot process electrical signals because it is a platypus.
The platypus’ bill detects the movement of the electrical signal, which is then processed by its brain.
Explanation
The passage explains that platypus use electroreception signals via their bills to locate prey. Their bill may first detect the signal, but their brains must process the signal to then begin their hunt. Remember that the brain processes all information received from the senses.