Question
Write down four characteristics of Ctenophora and give two examples.

Answer

  1. Transparent body with biradial symmetry.
  2. Two tentacles and eight longitudinal rows of ciliary comb-plates for locomotion are present.
  3. Marine, solitary and free-swimming.
  4. No polymorphism or dimorphism occurs.
Example: Pleurobrachia and Cestum.

Need a full question paper?

Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.

Start Generating Free

Similar questions

A farmer is advised to use manure instead of fertilizer in his fields. List any two advantages that the farmer will get if he accepts this advice. How is the use of manure particularly useful for clayey and sandy soil?
A liquid compound $X$ of molecular mass $18u$ can be obtained from a number of natural sources. All the animals and plants need liquid $X$ for their survival. When an electric current is passed through $200$ grams of pure liquid $X$ under suitable conditions, then $178$ grams of gas $Y$ and $22$ grams of gas $Z$ are produced. Gas $Y$ is produced at the positive electrode whereas gas $Z$ is obtained at the negative electrode. Moreover, gas $Y$ supports combustion whereas gas $Z$ burns itself causing explosions.
  1. Name $(i)$ liquid $X$ $(ii)$ gas $Y$, and $(iii)$ gas $Z$
  2. What is the ratio to the mass of element $Z$ to the mass of element $Y$ in the liquid $X$?
  3. Which law of chemical combination is illustrated by this example?
  4. Name two sources of liquid $X$.
  5. Gate an important use of $Y$ in our life.
What is endoplasmic reticulum? Give its types and functions.
Study the speed-time graph of a car given alongside and answer the following questions:


  1. What type of motion is represented by OA?
  2. What type of motion is represented by AB?
  3. What type of motion is represented by BC?
  4. What is the acceleration of car from O to A?
  5. What is the acceleration of car from A to B?
  6. What is the retardation of car from B to C?
Draw a well-labelled diagram of an eukaryotic nucleus. How is it different from nucleoid?
The mass of a planet is $6 \times 10^{24} \mathrm{~kg}$ and its diameter is $12.8 \times 10^3 \mathrm{~km}$. If the value of gravitational constant be $6.7 \times 10^{-11} \mathrm{Nm}^2 / \mathrm{kg}^2$, calculate the value of acceleration due to gravity on the surface of the planet. What planet could this be?
Write down four characters of mammals. Give two examples.
Classify each of the following as a physical or a chemical change. Give reasons.
i. Drying of a shirt in the sun.
ii. Rising of hot air over a radiator.
iii. Burning of kerosene in a lantern.
iv. Change in the colour of black tea on adding lemon juice to it.
v. Churning of milk cream to get butter.
Mention differences between light microscope and electron microscope.
Differentiate between flying lizard and bird. Draw the diagram.