Q: A solution has a pH of 4. What is the concentration of hydrogen ions $$[H^+] in $$this solution? Use the formula $$pH = -\log_{10}[H^+].$$

$$[H^+] = 1 \times 10$$^{-4}$$ \ \mathrm{M}$$

Question 1

Which of the following best describes the characteristic of life known as 'homeostasis'?

Accepted Answer

The ability of an organism to maintain a stable internal environment despite changes in external conditions.

Question 2

Which of the following correctly lists the levels of biological organization from smallest to largest?

Accepted Answer

Molecule, cell, tissue, organ, organism, population, community, ecosystem, biosphere

Question 3

A scientist observes that a certain plant grows faster when exposed to blue light compared to red light. She designs an experiment to test this observation. Which step of the scientific method is she performing?

Accepted Answer

Conducting an experiment

Question 4

Which of the following best explains how the theory of evolution accounts for the unity and diversity of life?

Accepted Answer

All living organisms share a common ancestor, but have diversified over time through descent with modification.

Question 5

Which of the following is an example of a producer in a biological community?

Accepted Answer

A maple tree converting sunlight into glucose through photosynthesis.

Question 6

Which of the following statements about chemical bonds is correct?

Accepted Answer

Ionic bonds involve the transfer of electrons from one atom to another.

Question 7

Water is essential for life due to its unique properties. Which property allows water to moderate Earth's climate by absorbing and releasing heat with only slight temperature changes?

Accepted Answer

High specific heat

Question 8

A solution has a pH of 4. What is the concentration of hydrogen ions $$[H^+] in $$this solution? Use the formula $$pH = -\log_{10}[H^+].$$

Accepted Answer

$$[H^+] = 1 	imes 10$$^{-4}$$ \ \mathrm{M}$$

Question 9

Which of the following best describes how a buffer works in a biological system?

Accepted Answer

A buffer minimizes changes in pH by accepting or donating hydrogen ions ($$H^+) $$when acids or bases are added.

Question 10

Which of the following is a correct statement about organic molecules?

Accepted Answer

Organic molecules are primarily composed of carbon atoms bonded to hydrogen, oxygen, nitrogen, and other elements.

Question 11

A patient is experiencing acidosis, where their blood pH drops below 7.35. Which of the following buffer systems is most important in maintaining blood pH?

Accepted Answer

The bicarbonate buffer system ($$H_2CO_3 \leftrightarrow $$HCO_3$$^- + H^+)$$

Question 12

Which of the following best explains why ice floats on liquid water?

Accepted Answer

Hydrogen bonds in ice create a lattice structure that is less dense than liquid water.

Question 13

Which of the following scenarios best illustrates the concept of descent with modification?

Accepted Answer

A population of finches develops different beak shapes over generations due to changes in available food sources.

Question 14

Which of the following is an example of a weak acid commonly found in biological systems?

Accepted Answer

Acetic acid ($$CH_3COOH)$$

Question 15

Which of the following best describes the role of experimental design in the scientific method?

Accepted Answer

It allows scientists to test hypotheses by controlling variables and collecting data.

Question 16

Which of the following is a correct application of the concept of producers and consumers in an ecosystem?

Accepted Answer

Grass (producer) is eaten by a rabbit (consumer), which is then eaten by a fox (consumer).

Question 17

Which of the following best explains why carbon is able to form such a wide variety of organic molecules?

Accepted Answer

Carbon can form four covalent bonds, allowing it to create complex and diverse molecular structures.

Question 18

A solution contains $$[OH^-] = 1 	imes 10$$^{-9}$$ \ \mathrm{M}. $$What is the pH of this solution? (Recall that $$pOH = -\log_{10}[OH^-]$$ and $$pH + pOH = 14)$$

Accepted Answer

$$pH = 5$$

Question 19

Which of the following is NOT a characteristic shared by all living things?

Accepted Answer

Ability to photosynthesize

Question 20

Which of the following best describes the relationship between a hypothesis and a theory in science?

Accepted Answer

A hypothesis is a testable explanation for an observation, while a theory is a well-supported explanation based on a large body of evidence.

Foundations of General Biology: Life, Evolution, Chemistry, and Water

Guida di studio - Domande di pratica

Study guide - Flashcard