Home
Class 12
BIOLOGY
How many points given below are correct ...

How many points given below are correct about Obelia?
(i) Radial symmetry
(ii) Diploblastic
(iii) Cellular level of organization
(iv) Digestion is intracellular only
(v) Exhibit two basic body forms called polyp and medusa.

A

Two

B

Three

C

Four

D

Five

Text Solution

AI Generated Solution

The correct Answer is:
To determine how many points are correct about Obelia, we will analyze each statement one by one: 1. **Radial symmetry**: - Obelia exhibits radial symmetry. This means that its body parts are arranged around a central axis, and it can be divided into similar halves by multiple planes. - **Conclusion**: This statement is **correct**. 2. **Diploblastic**: - Diploblastic organisms have two germ layers: the outer ectoderm and the inner endoderm. Obelia is indeed diploblastic. - **Conclusion**: This statement is **correct**. 3. **Cellular level of organization**: - Obelia does not have a cellular level of organization; instead, it has a tissue level of organization. This means that its cells are organized into tissues, which perform specific functions. - **Conclusion**: This statement is **incorrect**. 4. **Digestion is intracellular only**: - In Obelia, digestion occurs extracellularly in the gastrovascular cavity, not intracellularly. Therefore, this statement is not true. - **Conclusion**: This statement is **incorrect**. 5. **Exhibit two basic body forms called polyp and medusa**: - Obelia exhibits two distinct body forms: the polyp and the medusa, which is a characteristic of its life cycle. This is known as alternation of generations. - **Conclusion**: This statement is **correct**. Now, let's summarize the findings: - Correct statements: 1 (Radial symmetry), 2 (Diploblastic), and 5 (Exhibit two basic body forms). - Incorrect statements: 3 (Cellular level of organization) and 4 (Digestion is intracellular only). Thus, the total number of correct points about Obelia is **3**. ### Summary of Correct Points: 1. Radial symmetry - Correct 2. Diploblastic - Correct 3. Cellular level of organization - Incorrect 4. Digestion is intracellular only - Incorrect 5. Exhibit two basic body forms called polyp and medusa - Correct **Final Answer**: 3 points are correct about Obelia.
Promotional Banner

Similar Questions

Explore conceptually related problems

Which of the statements regarding coelenterates is/are wrong I. Cnidocytes are present on the tentacles and on the body II. Diploblastic with cellular level of organisation III. Polyp forms are free living IV. Exhibit metagenesis V. Polyps produce medusae sexually and medusae form polyps asexually.

Which of the statements regarding coelenterates is/are wrong I. Cnidocytes are present on the tentacles and on the body II. Diploblastic with cellular level of organisation III. Polyp forms are free living IV. Exhibit metagenesis V. Polyps produce medusae sexually and medusae form polyps asexually.

The characters given below are shown by (i) Extracellular and intracellular digestion (ii) Exclusively marine, radially symmetrical, diploblastic, tissue level of organisation (iii) Bisexual, fertilisation external and indirect development (iv) No asexual reproduction (v) Presence of comb plates

Given below are the general characters of a phylum .Identify the phulum . (i) Extracellular and intracellular digestion (ii) Tissue level of organization (iii) Indirect development (iv) No asexual reproduction

Which two of the below given points are known as the twin characteristics growth ? (i) Increase in mass (ii) Increase in number of individuals (iii) Cellular organisation (iv) Cellular differentiation

Choose how many of the given statement are not correct about the Tropics ? (i) Greater species diversity compared to Temperate (ii) Subjected to frequent glaciations in the past (iii) Great seasonal variations are seen here (iv) Enviornment is relatively constant

Mark te given statements True (T) or False (F) (i) All members of animalia are multicellular. (ii) Sponges exhibit tissue grade level of body organization (iii) A complete digestive system has two openings, mouth and anus. (iv) Annelids are pseudocoelomate animals. (v) notochord is an endodermally derived structure. (vi) all vertebrates are chordates. (vii) all chordates are vertebrates (viii) Polyps produce medusae asexually and medusae form the polyps sexually. (ix) Hooks and suckers are present in non parasitic flatworms (x) Lamprey dies after few days of spawning.

Identify the parts labelled as A,B,C and D in the given figure and match the correct names from the list (i-viii) given below. (i)Reissner's membrane , (ii)Basilar membrane (iii)Tectorial membrane , (iv)Organ of Corti (v)Hair cellls , (vi)Otolith organ (vii)Scala media , (viii)Scala vestibuli

How many of the following statements given are incorrect ? (i) Pusa Gaurav , a variety of Brassica , is disease resistant for bacteria . (ii) Jaya and Ratna are varieties of wheat . (iii) Method of producing thousands of plants through tissue culture is called micropropagation. (iv) pusa Sawani is a variety of Brassica . (v) Capacity to generate a whole plant from any cell explants is called totipotency.

Read the following statements :- (i) Ernst Mayr, has been called "The Mendel of the 20^(th) century. (ii) All living organisms grow (iii) Unicellular organisms multiply by cell division (iv) Non-living object also exhibits metabolism How many statement is/are correct ?