Life under microscope Q A

LIFE UNDER MICROSCOPE
Q1: Which of the following are organisms which can be macroscopic?
a) Bacteria
b) Fungi
c) Virus
d) Protozoa
Q2: Which of the following is not made using microorganisms?
a) Curd
b) Biscuits
c) Bhaji
d) Bread
Q3: How microorganisms are able to survive for years?
Ans: Because they remain inactive in spore form or show extra covering around them which protect them in harsh environments.
Q4: Answer in one word:
a) Name the group of microbes which are prokaryotic.
Ans: Bacteria
b) Which are the most abundant (mostly found) forms of life on earth?
Ans: Bacteria
c) Size of a bacterial cell
Ans: 0.2 to 100 micrometer
d) Locomotory structures present in bacterial cell
Ans: Flagella
e) Root like structure in fungi
Ans: Rhizoids
f) A fungus which do not have rhizoids.
Ans: Mucor
g) Name a protozoa that is autotrophic.
Ans: Euglena
h) Mushroom commonly consumed as food
Ans: Button and Oyster mushrooms
i) Virus causing common cold
Ans: Rhinovirus
j) Malaria is caused by protozoa
Ans: Plasmodium
k) Dengue is caused by
Ans: Dengue virus carried by Aedes mosquito
Q5: Match the following:
a) Coccus vibrio cholerae
b) Spirillum lactobacillus
c) Bacillus streptococcus
d) Vibrios minus
Q6: What is true for Thermoacidophiles?
a) Bacteria that survives in high temperature.
b) Bacteria that survives in acidic environment.
c) Microbes which survive in absence of oxygen
d) Bacteria that survive in high temperature and acidic environment.
Q7: Draw a labelled diagram of a bacterial cell.
Ans:
Q8: What is binary fission?
Ans: Binary fission is a method of reproduction in bacteria in which one cell divides and gives rise to two cells.
Q9: Match the following:
Ans: a) Spirogyra colonial
b) volvox hyphae
c) Chlamydomonas chlorophyll
d) Chlorella filamentous form
e) mycelium unicellular

Q10: Eukaryotic microorganisms which are best known for their saprophytic nutrition.
Ans: Fungi
Q11: Write one similarity and one difference between cell of fungi and algae.
Ans: Similarity: Both of them have presence of cell wall.
Difference: Algae have cholorophyll but fungi do not have.
Q12: Draw labelled diagram of Fungi.
Ans:
Q13:  What is one peculiar characteristic of protozoa?
Ans: They show good amount of mobility like animals. E.g. Amoeba, Paramecium and Euglena.
Q14: Name a microorganism which is neither alive nor to be dead.
Ans: Virus
Q15: Explain the structure of bacteriophage.
Ans: Bacteriophage is a virus that consists of following parts:
a) HEAD: A strand of nucleic acid ,DNA or RNA surrounded by a protective protein coat(the capsid).
b) NECK:  It has collar connecting neck with head surrounded by a sheath.
c) TAIL:  It has tail fibres attached with base plate of neck.
Q16: Diseases caused by Virus:
Ans: AIDS , Polio, Swine Flu, Common cold, Influenza.
Q17: What is Fermentation?
Ans: A process of producing acids, alcohol and many other products when microorganisms are allowed to respire and release gases such as carbon dioxide by mixing with food products. E.g. yeast (fungus) and Acetobacter (bacteria) are used for making Vinegar, alcohol, wine and fruit juices.
Q18:  Write benefits of mushrooms.
Ans: These are used in making soups and as toppings for pizzas. They are rich in protein and Vitamin B. They are good for health as they contain limited amount of fats and virtually free from Cholestrol.
Q19: How do lactobacilli make curd when mixed with Milk?
Ans: They produce lactic acid for the formation of curd.
Q20: Which of the following is not fermentation?
a) Formation of curd
b) Formation of vinegar
c) Formation of Iodine from brown algae
d) Formation of cakes
Q21: Which of the following is an incorrect match?
a. Anton van Leeuwenhoek — microorganisms
b. Alexander Fleming — penicillin
c. Edward Jenner — vaccination
d. Louis Pasteur — fermentation
Q22: Which of the following statements is incorrect?
a. Volvox is a variety of green algae. b. Iodine is obtained from brown algae.
c. Algae are microbes which lack chlorophyll. d. Diatoms have a cell wall made of silica.
Q23: Choose the correct option.
1. …………………….. have DNA and RNA as the generic material surrounded by a protein coat
(Viruses / Bacteria).
2. Introduction of a small amount of an antigen in the body is called ………………….
(immunization/ inoculation).
3. ………………… trap nitrogen from air and change it into nitrogenous compounds.
(Azotobacter/Aertobacter)
4. The proteinaceous covering surrounding the cell wall of a bacterium is called
………………….. (capsule / shell).
5. Curd is formed when a protein called …………………… present in milk coagulates and
forms a solid mass with the help of Lactobacillious acidophilus (casein / keratin)
6. Penicillin is obtained from fungus called ____________________.
7.
Q24: What is a vaccine?
Ans: A vaccine is a biological preparation that improves immunity to a particular disease. It consists of an agent that resembles a disease causing microorganism. It is often made from weakened or killed forms of the microbe, its toxins or proteins. The immune system responds to fight against these foreign bodies and produces special proteins called ANTIBODIES.
Q25: Write major uses of microbes.
Ans:1) Present inside stomach of ruminants and Human beings
2) Nitrogen fixing bacteria
3) Bacteria used in processing of leather
4) Production of Bio-gas
5) Agar obtained from Red and Brown algae is used for thickening soups and preparing Jellies.
6) Oil-eating bacteria like Pseudomonas
Q26: Write a note on harmful microbes.
Ans: Diseases causing microorganisms are called pathogens or germs. Some common diseases caused by microbes are cholera, common cold, tuberculosis, cancer etc. They can enter our body through various modes such as air, water and used clothes. They also get transmitted by direct contact or through a carrier.
Q27: What are methods of food preservation?
Ans: 1) Use of chemicals like SODIUM BENZOAE and POTASSIUM METABISULPHATE in squahes, sherbets and ketchups.
2) Salt and sugar for preserving fish and meat.
3) Drying decreases moisture in the food and increase the shelf life.
4) Canning in vacuum after heating at high temperature because lack of air restricts growth of microorganisms.
5) Pasteurization:  Sudden heating and cooling of milk kills and prevents multiplication of bacteria.
6) Radiation: To kill germs.