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Multiple choice c3, c4 and cam plants photosynthesis in higher plants biology

What is the primary acceptor of $CO _2$ in Hatch-Slack cycle?

  1. Phosphoenolpyruvic acid

  2. Ribulose biphosphate

  3. Phosphoglyceric acid

  4. Diphosphoglyceric acid
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

In the Hatch-Slack (C4) cycle, the primary CO2 acceptor is phosphoenolpyruvate (PEP). This reaction is catalyzed by the enzyme PEP carboxylase to form oxaloacetate.

Multiple choice c3, c4 and cam plants photosynthesis in higher plants biology

$C 4$ plants are divided into three subgroups based on ______________.

  1. Decarboxylation reactions

  2. Oxidation reactions

  3. Reduction reactions

  4. Energy reactions
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

C4 plants are classified into three subgroups based on the specific enzyme used for the decarboxylation of the C4 acid in the bundle sheath cells: NADP-ME, NAD-ME, and PEP-CK types.

Multiple choice c3, c4 and cam plants photosynthesis in higher plants biology

Which of the following photosynthetic characteristics are present in $C _3$ plants but not in $C _4$ plants?
a. $CO _2$ compensation point of $45$ ppm
b. Relatively higher rate of photo respiratory $CO _2$ evolution
c. Presence of well developed bundle sheath
d. Initial involvement of RuBP carboxyl's(RuBis CO) in $CO _2$ assimilation.
Select the correct answer using the codes given.

  1. $1, 2$ and $3$
  2. $1, 2$ and $4$
  3. $1, 3$ and $4$
  4. $2$ and $4$
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

C3 plants possess a higher CO2 compensation point, a higher rate of photorespiration, and initially use RuBisCO for carbon fixation via the Calvin cycle. Bundle sheath cells are characteristic of C4 plants, not C3 plants, which lack Kranz anatomy.

Multiple choice c3, c4 and cam plants photosynthesis in higher plants biology

$C _4$ plants are more efficient in photosynthesis than $C _3$ plants because of.

  1. Higher leaf area

  2. The presence of a large number of chloroplasts

  3. The presence of a thin cuticle on the leaf surface

  4. Lower photorespiration
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

C4 plants are more efficient than C3 plants primarily because they virtually eliminate photorespiration. They concentrate CO2 around RuBisCO in bundle sheath cells, preventing the oxygenase activity that wastes fixed carbon.

Multiple choice c3, c4 and cam plants photosynthesis in higher plants biology

$C 3$ and $C _4$ and CAM plant species are found in _________.

  1. Crassulaceae

  2. Cactaceae

  3. Euphorbiaceae

  4. Poaceae
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

The family Crassulaceae is famous for containing species that exhibit CAM photosynthesis, but C3 and C4 species are also found within this diverse family.

Multiple choice c3, c4 and cam plants photosynthesis in higher plants biology

Reductional division involves _________________.

  1. Separation of non-sister chromatins

  2. Reduction of chromosome number

  3. Separation of sister chromatics

  4. Crossing over
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Reductional division refers to meiosis I, where homologous chromosomes separate, resulting in a reduction of the chromosome number from diploid to haploid. Mitosis and meiosis II are equational divisions where sister chromatids separate.

Multiple choice c3, c4 and cam plants photosynthesis in higher plants biology

The fixation of $CO 2$ to malate and its decarboxylation are conunon to both $C _4$ and  $CAM$ plants, but in $CAM$ plants these events _____________.

  1. Are separated spatially

  2. Are separated temporally

  3. Require high light intensity
  4. Require high $CO _2$ concentration
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Both C4 and CAM plants fix CO2 into organic acids like malate via PEP carboxylase. However, while C4 plants separate these steps spatially between mesophyll and bundle sheath cells, CAM plants separate them temporally between day and night.

Multiple choice c3, c4 and cam plants photosynthesis in higher plants biology

Choose the correct answers from the alternatives given.
Cyanobacteria, unlike other types of bacteria that photosynthesize, do:

  1. not have a cell wall

  2. not have chlorophyll

  3. give off oxygen

  4. not give off oxygen
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation
Cyanobacteria, also called blue-green algae, were among the earliest organisms on Earth. These primitive bacteria produce oxygen during photosynthesis as they fix CO$ _2$ dissolved in the water. So the correct option is 'Give off oxygen’.
Multiple choice c3, c4 and cam plants photosynthesis in higher plants biology

If 24G-3-P molecules are formed in ${ C } _{ 3 }$ plants.Calculate a) the number of $CO _{ 2 }$ used and b) the number of G3P used for regeneration RuBP molecules

  1. $a=12, b=20$
  2. $a24, b=48$
  3. $a=12, b=24$
  4. $a=20, b=12$
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

In carbon fixation 5 molecules of C)@ are combines or fixed with 6 molecules; Ribulose Bisphosphate(RuBP) to make 12 molecules of PGA.

The remaining 20 G3P molecules regenerate RuBP, which enables the system to prepare for the carbon fixation step.
So, the correct option is 'a = 12, b = 20'.

Multiple choice c3, c4 and cam plants photosynthesis in higher plants biology
Kranz anatomy is not exhibited by which of the following plants?

  1. Maize

  2. Sorghum

  3. Sugarcane

  4. Sunflower
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Kranz anatomy is observed in $C _4$ grasses like Maize, Sorghum and Sugarcane. This is to reduce the inefficiencies of RuBisCO that can catalyse the reaction with $O _2$ rather than $CO _2$ resulting in photorespiration than photosynthesis. To overcome this, $CO _2$ is first as a four carbon compound and then made available to RuBisCO, This is a spatial and temporal separation of reactions into bundle sheath cells and a ring of mesophyll cells surrounding the bundle sheath. Sunflower has only $C _3$ cycle of photosynthesis and does not exhibit Kranz anatomy.

So, the correct answer is 'Sunflower'