13. Which components of DNA are held together by weak hydrogen bonds?

Essential nutrients move through a cell membrane by both passive transport and active transport. Which of the following correctl

Inessa [10]

Answer: A). Active transport requires chemical energy to move nutrients from areas of low concentration to areas of high concentration.

Explanation:

Sometimes cells require nutrients such as sodium and potassium to be transported from an area where they are in low concentration to an area where they are in high concentration.

This goes against the concentration gradient where substances are transported from an area of high concentration to one with low concentration as is the case in processes such as osmosis.

This process is called Active transport and describes the use of chemical energy to move nutrients from areas of low concentration to areas of high concentration.

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3 years ago

11.1 The Science of Ecology Lesson 11.1: True or False Name __________________ Class ______________ Date ________ Write true if

tangare [24]

Answer:

See explanation below

Explanation:

1. Biotic factors include sunlight, soil, temperature, and water. FALSE

Biotic factors include animals, plants, fungi, bacteria and protists.

2. Like nutrients and water, energy also recycles through an ecosystem. FALSE

3. An ecosystem consists of all the biotic and abiotic factors in an area and their interactions. TRUE

4. Herbivores are a necessary link between producers and other consumers. TRUE

5. A niche refers to the place an organism lives within its ecosystem. TRUE

6. Dung beetles eat animal feces. TRUE

7. Autotrophs make their own food. TRUE

8. Organisms use 90% of the available energy at each trophic level. FALSE

9. Carnivores include lions, polar bears, hawks, frogs, salmon, and deer. FALSE

Deer is a herbivore.

10. Biomass increases at the upper levels of a food chain. FALSE

11. Producers occupy the first trophic level. TRUE

12. Scavengers include vultures and raccoons. TRUE

13. In a complex ecosystem, it is likely that two different species will occupy the same niche. FALSE

14. The habitat is the role of a species in its ecosystem. FALSE

15. A food web shows how energy flows through an ecosystem. TRUE

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3 years ago

4. What other word from paragraph 2 most

sesenic [268]

Answer:

d

Explanation:

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3 years ago

During the nineteenth century, sea otters were hunted almost to the point of extinction. when the number of sea otters became ve

jonny [76]

They ensured that balance in the ecosystem was maintained. They ensure that the genetic diversity and species is maintained. Sea otters applied natural selection pressures on the sea urchins population hence maintaining their level such that they will not overgraze on the kelps. Overgrazing would severely affect the sea urchin population and consequently severely affect the sea otters population too.

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3 years ago

Compare and contrast cell differentiation in plant and animal cells

balandron [24]

The cells are generally the same but animal cells don't have a cell wall and also there vacuole is smaller than plants

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3 years ago