Question:
In a marine ecosystem, a specific brown alga is found to possess air bladders to maintain buoyancy near the water surface. This plant is likely:
In a marine ecosystem, a specific brown alga is found to possess air bladders to maintain buoyancy near the water surface. This plant is likely:
Show Hint
Air bladders (pneumatocysts) are characteristic evolutionary structures of Phaeophyceae (brown algae). Think of Fucus and Sargassum as prime examples of floating brown seaweeds with these structures.
Updated On: Jun 3, 2026
- Polysiphonia
- Fucus
- Gelidium
- Porphyra
Show Solution
Verified By Collegedunia
The Correct Option is B
Solution and Explanation
Step 1: Understanding the Question:
The question asks us to identify a marine brown alga (class Phaeophyceae) that possesses air bladders. These gas-filled structures are specialized morphological adaptations that provide buoyancy, helping the alga stay afloat near the water surface to maximize sunlight exposure for photosynthesis.
Step 2: Detailed Explanation:
• Brown algae, belonging to the class Phaeophyceae, are primarily marine plants. They are distinguished by their olive-green to brown colors, which depend on the concentration of the xanthophyll pigment, fucoxanthin, in addition to chlorophyll $a$ and $c$.
• Many large brown algae, such as Fucus and Sargassum, have evolved specialized air-filled floats called air bladders or pneumatocysts. These bladders keep the photosynthetic lamina floating near the photic zone where light is abundant.
• Polysiphonia is a genus of marine red algae (class Rhodophyceae) characterized by its filamentous structure. It does not possess air bladders.
• Gelidium is another genus of red algae. It is well known as a primary source of agar-agar, which is used to prepare culture media in microbiology, but it lacks air bladders.
• Porphyra is a red alga commonly used as food (such as nori in sushi). It is a leafy thallus without air bladders.
• Therefore, among the choices provided, Fucus is the only brown alga that possesses air bladders.
Step 3: Final Answer:
The marine brown alga containing air bladders for buoyancy is Fucus.
The question asks us to identify a marine brown alga (class Phaeophyceae) that possesses air bladders. These gas-filled structures are specialized morphological adaptations that provide buoyancy, helping the alga stay afloat near the water surface to maximize sunlight exposure for photosynthesis.
Step 2: Detailed Explanation:
• Brown algae, belonging to the class Phaeophyceae, are primarily marine plants. They are distinguished by their olive-green to brown colors, which depend on the concentration of the xanthophyll pigment, fucoxanthin, in addition to chlorophyll $a$ and $c$.
• Many large brown algae, such as Fucus and Sargassum, have evolved specialized air-filled floats called air bladders or pneumatocysts. These bladders keep the photosynthetic lamina floating near the photic zone where light is abundant.
• Polysiphonia is a genus of marine red algae (class Rhodophyceae) characterized by its filamentous structure. It does not possess air bladders.
• Gelidium is another genus of red algae. It is well known as a primary source of agar-agar, which is used to prepare culture media in microbiology, but it lacks air bladders.
• Porphyra is a red alga commonly used as food (such as nori in sushi). It is a leafy thallus without air bladders.
• Therefore, among the choices provided, Fucus is the only brown alga that possesses air bladders.
Step 3: Final Answer:
The marine brown alga containing air bladders for buoyancy is Fucus.
Was this answer helpful?
0
0
Top AP EAPCET Botany Questions
- Plant that possess characters like ramenta, archegonia, circinate
- Identify the correct pair from the following
A. Golden algae - diatoms
B. Trichodesmium erythrium - Red Sea
C. Kieselguhr - Chrysophytes
D. Red tides of Mediterranean sea - Dinoflagellates - Assertion (A): Fertilization in Cycas is called siphonogamy and zooidogamy.
Reason (R): Male gametes are multiciliate and carried by pollen tube. - Identify the organisms based on their cell wall characteristics such as pseudomurein, mycolic acid, stiff cellulose plates, chitin.
- Find the correct matching
A) Carrot -- Flowers appear from the same point of peduncle
B) Cocos -- Flowers protected by the modified bract
C) Achyranthes -- Flowers appear in the varied lengths of pedicels
D) Cassia -- Flowers appear on the flattened peduncle
View More Questions
Top AP EAPCET Plant Kingdom Questions
- Plant that possess characters like ramenta, archegonia, circinate
- Following is not applicable in terms of plant-water relations, if a seed is soaked in water
- Choose the correct statements
a. Inability of seed germination due to immature embryo is called Quiescence.
b. Seed coats of Fabaceae do not absorb $O_{2}$ and $H_{2}O$.
c. Germination of tomato seeds is inhibited by chemical compounds.
d. Seeds of polygonum require exposure to low temperature. - Assertion (A): Epidermis of hydrophytes is useful for absorption and assimilation.
Reason (R): In hydrophytes, epidermal cells are devoid of cuticle and contain chloroplasts. - The following plant is submerged and suspended in water
View More Questions
Top AP EAPCET Questions
- A body is projected from the ground at an angle of $\tan^{-1} \left( \frac{8}{7}\right)$ with the horizontal. The ratio of the maximum height attained by it to its range is
- The four quantum numbers of the valence electron of potassium are :
- A lens forms real and virtual images of an object, when the object is at $u_{1}$ and $u_{2}$ distances respectively. If the size of the virtual image is double that of the real image, then the focal length of the lens is (take, the magnification of the real image as $m$ )
- Two spheres $P$ and $Q$, each of mass $200\, g$ are attached to a string of length one metre as shown in the figure. The string and the spheres are then whirled in a horizontal circle about $O$ at a constant angular speed. The ratio of the tension in the string between $P$ and $Q$ to that of between $P$ and $O$ is $(P$ is at mid-point of the line joining $O$ and $Q$ )
- The volume of $0.02\, M$ acidified permanganate solution required for complete reaction of $60\, mL$ of $0.01\, MI^{-}$ ion solution to form $I_2$ in $mL$ is
View More Questions