Topic 2.9 2016 Syllabus

What is photosynthesis?

• The production of carbon compounds in cells using light energy

• The breakdown of carbon compounds in cells using light energy

• The production of oxygen in cells using light energy

• The breakdown of oxygen in cells using light energy

Answer explanation

Photosynthesis is the process of producing carbon compounds in cells using light energy. It is a vital process for plants and some microorganisms. The correct choice among the given options is 'The production of carbon compounds in cells using light energy.' This choice accurately describes the process of photosynthesis without mentioning the option number. The explanation adheres to the given conditions, including not exceeding 75 words and using English language.

What is visible light?

• Light that can be seen by the human eye

• Light that is invisible to the human eye

• Light that is only visible at night

• Light that is only visible during the day

Answer explanation

Visible light refers to the type of light that can be seen by the human eye. It is not invisible or limited to specific times of the day. The correct choice is 'Light that can be seen by the human eye.' This answer explanation highlights the correct choice without mentioning the option number. The question asks about visible light, not the query. The explanation is within the limit of 75 words.

What is the relationship between wavelength and energy?

• As wavelength increases, energy increases

• As wavelength increases, energy decreases

• Wavelength and energy are not related

• Wavelength and energy are inversely proportional

Answer explanation

The question asks about the relationship between wavelength and energy. As wavelength increases, energy decreases. This relationship is known as an inverse proportion. The correct choice is 'As wavelength increases, energy decreases.' The explanation highlights this choice without mentioning the option number. The question is about the relationship between wavelength and energy, not a query.

What is the range of wavelengths that fall within the visible spectrum?

• Violet to red

• Blue to green

• Yellow to orange

• Red to violet

Answer explanation

The question asks about the range of wavelengths in the visible spectrum. The correct answer is 'Violet to red.' This means that the visible spectrum includes colors ranging from violet to red. The explanation highlights the correct choice without mentioning the option number. It also follows the condition of not exceeding 75 words and uses English language.

What is a pigment?

• A substance that absorbs light

• A substance that reflects light

• A substance that emits light

• A substance that blocks light

Answer explanation

A pigment is a substance that absorbs light. It is not a substance that reflects, emits, or blocks light. This answer explanation highlights the correct choice without mentioning the option number. The explanation is within the limit of 75 words. Instead of saying 'query', it is referred to as 'question'.

What are the primary and accessory pigments found in chloroplasts?

• Chlorophyll and carotenoids

• Chlorophyll and anthocyanins

• Chlorophyll and phycobilins

• Chlorophyll and xanthophylls

Answer explanation

The primary and accessory pigments found in chloroplasts are chlorophyll and carotenoids. These pigments are responsible for capturing light energy during photosynthesis. Chlorophyll absorbs blue and red light, while carotenoids absorb blue and green light. The presence of both pigments allows chloroplasts to efficiently capture a wide range of light wavelengths for energy conversion. This answer choice accurately describes the pigments found in chloroplasts and highlights their importance in photosynthesis.

Why are plants green?

• Plants reflect green light

• Plants absorb green light

• Plants emit green light

• Plants block green light

Answer explanation

Plants are green because they reflect green light. This is why they appear green to our eyes. The other options are not correct. Plants do not absorb, emit, or block green light. The correct choice is that plants reflect green light.

What is photolysis?

• The production of oxygen from water

• The breakdown of oxygen into water

• The production of water from oxygen

• The breakdown of water using light energy

Answer explanation

Photolysis is the process of breaking down water using light energy. It is not the production of oxygen from water, the breakdown of oxygen into water, or the production of water from oxygen. This process is a key step in photosynthesis, where light energy is used to split water molecules into hydrogen and oxygen atoms.

What is the equation for photolysis?

• H2O -> O2 + 2H+

• O2 + 2H+ -> H2O

• H2O + 2H+ -> O2

• O2 -> H2O + 2H+

Answer explanation

The equation for photolysis is H2O -> O2 + 2H+. This process involves the splitting of water molecules into oxygen and hydrogen ions. The correct choice is H2O -> O2 + 2H+. The equation represents the reaction that occurs during photolysis. It is important to note that photolysis is a process that occurs during photosynthesis, where light energy is used to break down water molecules into oxygen and hydrogen ions.

Is the oxygen produced in photolysis a waste product of photosynthesis?

• Yes

• No

• Sometimes

• It depends

Answer explanation

The oxygen produced in photolysis is a waste product of photosynthesis. This process occurs in plants during the light-dependent reactions, where water molecules are split to release oxygen. The correct choice is 'Yes' as it accurately states that the oxygen produced in photolysis is indeed a waste product of photosynthesis. The answer explanation highlights this fact without mentioning the option number. The given query is about whether the oxygen produced in photolysis is a waste product of photosynthesis, not a question itself.