CBSE Class 9 Biology Diversity In Living Organisms Worksheet Set A

Question. What are autotrophic bacteria? Give an example for autotrophic bacteria.
Ans : The bacteria which synthesize their own food from inorganic substances are called autotrophic bacteria.
Example : Nostoc, Anabaena.

Question. What are heterocysts?
Ans : The colourless specialized cells of nostoc filament meant for fixing atmospheric nitrogen are called heterocysts.

Question. What are chemosynthetic autotrophic bacteria?
Ans : The bacteria which oxidize inorganic substances like nitrate, nitrities and ammonia to release energy in the form of ATP are called chemosynthetic bacteria.

Question. What are mycoplasmas?
Ans : The smallest living organisms without cell walls and survive without oxygen are called mycoplasmas.

Question. What are planktons?
Ans : The microscopic organisms which floats on water are called planktons.

Question. Name the chemical component of cell wall of Diatoms.
Ans : Chitin.

Question. What are euglenoids?
Ans : The fresh water organisms found in stagnant water with protein rich particle in their cell wall are called euglenoids.

Question. What are plasmodium?
Ans : Aggregation of slime moulds under suitable conditions are called plasmodium, which may grow and spread over several feet. During unfavorable conditions they differentiate and follows fruiting bodies.

Question. Name parasitic protozoa.
Ans : Entamoeba, Plasmodium (Malarial parasite).

Question. Name the disease caused by Trypanosoma.
Ans : Sleeping sickness.

Question. What are the characteristic features of mammals?
Ans : Characteristic features of mammals :
(a) Body is covered with hair.
(b) Skin is provided with sweat and sebaceous glands.
(c) Heart is four-chambered.
(d) Fertilization is internal.
(e) Females have mammary glands to produce milk to nourish their young ones.
(f) External ear–pinna present.
(g) Eyes have eye lids.
(h) Warm-blooded.
(i) Respiration through lungs.

Question. What is the importance of heterotrophic bacteria?
Ans :
(1) Conversion of milk to curd.
(2) Antibiotic productions.
(3) N2 fixation in leguminous roots.
(4) Act as pathogen, causing diseases like cholera, typhoid, tetanus.
(5) Damage corps (citrus canker disease)
(6) Act as ‘Scavengers of nature’ by decomposing dead and decaying organic matter.

Question. Name the 2 methods of protistan’s reproduction.
Ans : (1) Asexual reproduction (cell fusion),
(2) Sexual reproduction (zygote formation).

Question. What are prokaryotes? Give one example for prokaryote.
Ans : The organisms which do not have well organized nucleus in their cell are called prokaryotes. Organisms containing incipient nucleus (Nucleoid) in their cells are called prokaryotes. Example : Bacteria, Nostoc (cyano bacteria/ B.G. Algae)

Question. Give one example for ciliated protozoans.
Ans : Paramecium.

Question. Which one is called malarial parasite?
Ans : Plasmodium.

Question. Name the disease caused by plasmodium.
Ans : Malaria.

Question. Which fungi act as a source of antibiotics?
Ans : Penicillium.

Question. What are saprophytic fungi?
Ans : The heterotrophic fungi which absorb soluble organic matter from dead substrates are called saprophytes.

Question. How are pores or holes all over the body of Porifera important?
Ans : The pores present all over the body of the organisms lead to a canal system that helps in circulating water throughout the body to bring in food and oxygen.

Question. If you are provided seeds of gram, wheat, rice, pumpkin, maize and pea. Classify these as Monocots/ Dicots.
Ans : Monocots : Wheat, Rice, Maize. Dicots : Gram, Pumpkin, Pea.

Question. What are hermaphrodites? Give two examples.
Ans : Hermaphrodites are the organisms that have both the sexes. Thus, it can produce both sperms and eggs and called hermaphrodites. Example : Sponges, earthworms.

Question. Give general characteristics of Porifera.
Ans :
(a) Animals with pores all over the body.
(b) Body is not well differentiated.
(c) Non-motile animals remain attached to solid support.
(d) Body is covered with hard outer skeleton. Example : Sponges.

Question. Give the characteristics of Arthropoda with 2 examples.
Ans :
(a) Arthropoda means jointed legs.
(b) Animals are bilaterally symmetrical and segmented.
(c) It has an open circulatory system.
(d) This is the largest group of animals.
Examples : Spider, scorpions, crabs, house flies.

Question. Give the characteristics of Ayes.
Ans : (a) Aves/birds can fly.
(b) Streamlined body.
(c) Hollow and light bones.
(d) Forelimbs are modified into wings.
(e) Warm-blooded animals, heart with four chambers.
(f) Egg laying animals.
(g) Beak present, teeth are absent.

Question. Write briefly about lichens.
Ans :
(1) Lichens are symbiotic close association of two different organisms such as algae and fungi.
(2) Algal component of lichen known as phycobiont which is photosynthetic in nature.
(3) Fungal component of living form is known as mycobiont which is non-photosynthetic, but helps in absorption of minerals, nutrients and water.
(4) Lichens are very good pollution indicator as they do not grow in polluted areas.
Question. Define species.
Ans : Species are organisms within genus with slight difference from other and capable of breeding and perpetuate.

Question. What is symbiotic relationship?
Ans : It is a relationship between two organisms in which both of them are benefitted, e.g., fungi gets food from blue-green algae and in return blue-green gets shelter (lichens).

Question. What is saprophytic nutrition?
Ans : The organisms that use dead and decaying organic matter as mode of nutrition is known as saprophytic nutrition.

Question. Name the plant amphibian.
Ans : Bryophyta, e.g. funaria.

Question. What are cryptogamae?
Ans : The plants with hidden reproductive organs are called cryptogamae, e.g., fern.

Question. Which divisions of the plant kingdom are called cryptogams? Why are they called so?
Ans : Thallophyta, Bryophyta and Pteridophyta divisions of plant kingdom are called cryptogamae. All these divisions have hidden reproductive organs.

Question. What are angiosperms?
Ans : Angiosperms are the group of plants with covered seeds. These are flowering plants.

Question. What is the meaning of triploblastic?
Ans : Animals which have three layers of cells : ectoderm, mesoderm and endoderm from which differentiated tissues can be made, e.g. tapeworm.

Question. What is bilateral symmetry?
Ans : Anything is said to have bilateral symmetry if its body have same design in left and right halves of the body.

Question. What do you mean by “cold-blooded animals”?
Ans : Cold-blooded animals are the animals that show the variation in their body temperature according to the surroundings, e.g., fish, amphibians, reptiles.

Question. Name a fish with skeleton made up of cartilage.
Ans : Shark.

Question. What is taxonomy?
Ans : The systematic study of identification, classification and naming of oraganisms is called taxonomy.

Question. Name the 2 kingdoms of classification?
Ans : (1) Plantae or Metaphyta
(2) Animalia or Metazoa

Question. What are Eukaryotes? Give an example of Eukaryotes?
Ans : Organisms which have well organized nuclei (True nucleus) are called Eukaryotes.
Example : Amoeba, mango, Man.

Question. What are multicellular organisms? Give an example for multi cellular organisms.
Ans : Organisms whose body is made up of many numbers of cells are called multicellular organisms.
Example : Spirogyra, Mango, Man.

Question. Who proposed five kingdom classification?
Ans : R.H. Whittaker (1969).

Question. What are Monerans?
Ans : Prokaryotic celled, unicellular and Autotrophic organisms.

Question. Name the kingdom which includes Bacteria.
Ans : Kingdom Monera.

Question. What is diatomaceous earth?
Answer : Accumulation of cell wall deposition of dead diatoms.