Maharashtra Board SSC Class 10 Science 2 Question Paper July 2023 with Answers Solutions Pdf Download.
SSC Science 2 Question Paper July 2023 with Answers Pdf Download Maharashtra Board
Time: 2 Hours
Total Marks: 40
Note:
- All questions are compulsory.
- The numbers to the right of the questions indicate full marks.
- Answer to every main question must start on a new page.
- In case of MCQs (Q. No. 1(A)) only the first attempt will be evaluated and will be given credit.
- For every MCQ, the correct alternative (A), (B), (C) or (D) with sub-question number is to be written as an answer.
For Eg.: (i) (A), (ii) (B), (iii) (C) or (iv) (D) - Scientifically correct and labelled diagrams should be drawn wherever necessary.
- Each answer must have correct question number and sub-question number.
Question 1.
(A) Choose the correct alternative and write the correct option: [5]
i. Genetic disorder like sickle cell anemia may be caused due to _________. (A)
(A) mutation
(B) translation
(C) translocation
(D) transcription
Answer:
(A) mutation
ii. Protein like interleukin produced by biotechnology is used against _________ disease. (B)
(A) anemia
(B) cancer
(C) diabetes
(D) haemophilia
Answer:
(B) cancer
iii. We get _________ of energy from one gram of lipid. (D)
(A) 9 cal
(B) 4 kcal
(C) 4 cal
(D) 9 kcal
Answer:
(D) 9 kcal
iv. The _________ bacteria are useful for cleaning the hydrocarbons and oil pollutants from soil and water. (C)
(A) Lactobacilli
(B) Acidobacillus
(C) Pseudomonas
(D) Streptococcus
Answer:
(C) Pseudomonas
v. Human males have _________ numbers of chromosomes. (B)
(A) 44 + XX
(B) 44 + XY
(C) 22 + XY
(D) 22 + XX
Answer:
(B) 44 + XY
(B) Answer the following: [5]
i. Pick the odd man out:
β-carotene, lycopenes, xylitol, lutein.
ii. Identify the phylum of the given animal:
iii. Complete the given flow chart
iv. State, if True or False:
Communication media like mobile phone, television, internet should be used often.
v. Write the co-relation:
Ovary : Estrogen :: Testes: ……….
Answer:
i. Xylitol
SMART TIP
Xylitol is used as artificial sweetener, whereas rest are used as edible colours.
ii. The given animal belongs to the phylum -Mollusca
iii. Embryonic stem cells
iv. False.
Communication media like mobile phone, television, internet should be used for essential needs and entertainment only.
v. Testosterone
SMART TIP
Recognize the biological correlation between the organs and their associated hormones. In this case, the ovary produces estrogen, so the testes would produce “Testosterone.”
Question 2.
(A) Give scientific reasons (any two): [4]
i. Duck billed platypus is a connecting link.
ii. Biofuel is important among the renewable sources of energy.
iii. Humans have a crucial role in maintaining environmental balance.
(B) Answer the following (any three):
i. Draw a neat and labelled diagram of mitochondria and tri-carboxylic acid cycle.
ii. Write any two objections that were raised against Darwin’s Theory of Natural Selection.
iii. Observe the given animal and answer the following questions:
(a) Identify the given animal and its phylum.
(b) Write any two characteristics of that phylum.
iv. Write any two objectives of disaster management.
v. Complete the given conceptual chart:
.
Answer:
(A)
i. a. Connecting links are some plants or animals that show morphological characters by which they can be related to two different groups of organisms.
b. The duck-billed platypus is a connecting link between mammals and reptiles as it shows similarity with mammals due to the presence of mammary glands and hairs and it lays eggs like reptiles.
ii. a. The sources of energy which are being produced continuously in nature and are inexhaustible, i.e., they are always available for use are called renewable sources of energy.
b. Biofuels are available in solid (dung, crop residue), liquid (vegetable oils, alcohol) and gaseous (gobar gas) forms.
c. Biofuels are easily available in sufficient amounts.
d. They are reliable fuels of the future.
Hence, Biofuel is important among the renewable sources of energy.
iii. a. Human life is an integral part of nature and human survival is closely linked with the environment.
b. Due to rapid increase in human population and industrialization, humans have over utilized natural resources; leading to degradation of environment.
c. The environment influences the life of human beings and also human beings modify their environment as humans are the apex predators in the food chain.
d. Humans are capable of conserving and improving the quality of nature and thus, can play a major role in maintaining environmental balance.
Humans therefore have a crucial role in maintaining environmental balance.
(B) i.
ii. Some of the main objections raised against Darwin’s theory of natural selection are as follows:
a. Natural selection is not the only factor responsible for evolution.
b. In his theory, Darwin did not explain the inheritance of useful and useless modifications.
c. No explanation regarding slow and abrupt changes was provided in this theory.
iii. a. The given animal is Balanoglossus. It belongs to the phylum Hemichordata.
b. Characteristics of the phylum Hemichordata:
1. Body of these animals is divided into three parts as proboscis, collar & trunk.
2. Notochord is present in proboscis region only. Hence, they are called as hemichordates.
3. These animals are also called as ‘acorn worms’.
4. These are marine animals, live in burrows in sand.
5. They have one to many pharyngeal gill slits.
6. They are unisexual or some may be hermaphrodite.
iv. The objectives of disaster management are as follows:
a. To reduce the loss of human life caused during the disaster and to rescue people from those disasters.
b. To reduce the effect of disaster by supplying essential commodities to people.
c. To restore the human life in the region and bring normalcy in life of people affected by disaster.
d. To rehabilitate the people affected by disaster.
e. To take precautionary steps so as to reduce the effect of similar disasters in future.
v.
Question 3.
Answer the following questions (any five): [15]
i. Observe the given figures and answer the following:
Identify the types of body symmetry and give one example of each apart from the given figure.
ii. Write a short note on — The types of Biodiversity.
iii. Complete the given chart:
| Body Constituents | Proteins/Amino Acids |
| 1. Blood | ………….. |
| 2. ………….. | Ossein |
| 3. Skin | ………….. |
| 4. ………….. | Insulin |
| 5. Muscle | ………….. |
| 6. ………….. | Various proteins of cell membrane |
iv. Rearrange and write proper alphabetical sequence only and complete the given blanks:
v. (a) Complete the given flow chart for electrical energy production based on thermal power plant.
(b) Complete the flow chart for energy transformation in thermal power plant.
vi. Complete the paragraph with the help of words given in the bracket:
(nutritive, ethanol, salt, actinomycetes, fermentation, carbon dioxide, lactic acid, Saccharomyces cerevisiae)
Different types of breads are produced from flour of cereals. Dough is formed by mixing of baker’s yeast – ………., water, ………. and other necessary materials with flour. Due to ………. of carbohydrates by yeast, sugar is converted into ………. and ………. . Dough rises up due to CO2 and the bread becomes spongy. Bread and other products produced with the help of yeast become ………. .
vii. Fill in the blanks in the structure of Disaster Management Authority.
viii. (a) Write any two advantages and two problems associated with hydroelectric power plant.
(b) Is hydroelectric power generation environment friendly? What is your opinion?
Answer:
i. A. Body symmetry: Asymmetrical body
Examples: Amoeba, Paramoecium, some sponges
B. Body symmetry: Radial symmetry Example: Starfish
C. Body symmetry: Bilateral symmetry
Examples: Insects, fishes, frog, birds, human, etc.
ii. a. Biodiversity is the richness of living organisms in nature due to the presence of varieties of organisms, ecosystems and genetic variations within a species.
b. Biodiversity occurs at three different levels.
1. Genetic diversity: It refers to the occurrence of diversity among organisms of same species.
e. g. Each human being is different from other.
2. Species diversity: It refers to the innumerable species of organisms that occur in nature.
e. g. Variety of plants, animals and microbes.
3. Ecosystem diversity: It refers to variation in ecosystems present in nature. These ecosystems are formed by the interaction between plants, animals, their habitats and changes in the environment. Each ecosystem has its own biotic (animals, plants, microbes) and abiotic factors.
iii.
| Body Constituents | Proteins/Amino Acids |
| 1. Blood | Hemoglobin and antibodies |
| 2. Bones | Ossein |
| 3. Skin | Melanin and keratin |
| 4. Pancreas | Insulin |
| 5. Muscle | Actin and myosin |
| 6. Cells | Various proteins of cell membrane |
iv. a. Correct alphabetical sequence: B—E—D—A—C
b. B: Isolation of desired gene from human pathogen
E: Transgenic plant virus (plant transformation vector with desired gene)
v.
vi. Different types of breads are produced from flour of cereals. Dough is formed by mixing of baker’s yeast – Saccharomyces cerevisiae, water, salt and other necessary materials with flour. Due to fermentation of carbohydrates by yeast, sugar is converted into carbon dioxide and ethanol. Dough rises up due to CO2 and the bread becomes spongy. Bread and other products produced with the help of yeast become nutritive.
vii.
viii. Advantages of hydroelectric power plant:
- No fuel is burnt in a hydroelectric power plant. Thus, no air pollution due to combustion of fuel occurs.
- Electricity can be generated whenever required if the dam has sufficient water storage.
- During rainy season, the water in the water reservoirs can be replenished and used for power generation.
Disadvantages of hydroelectric power plant:
- Villages, towns, forests may submerge due to back-water caused by storage of water in dams. This leads to forced migration of the living population in that area.
- The obstruction of the flow of river water may have adverse effect on the living world in the river.
b. Hydroelectric power plant offers the advantage of providing clean and renewable electricity without the need for the combustion of fossil fuel, but the construction and operation of hydroelectric power plants can cause damage to wildlife habitats and have an adverse effect on the living world in the river.
Question 4.
Answer the following (any one): [5]
i. Answer the following questions in complete sentence based on female reproductive system:
(a) How many immature oocytes are present at the time of birth in the ovary of female foetus?
(b) What is ovulation?
(c) What is menopause?
(d) Draw scientifically correct diagram of female reproductive system.
(e) Label the following parts:
(i) Ovary
(ii) Uterus
ii. (a) Complete the flow chart:
(b) Observe the following pictures and answer the following:
(i) Whether the incidence shown in the picture is rational or irrational? Justify your answer.
(ii) Identify the picture. What is the punishment given to the person shown in the picture?
Answer:
i. a. At the time of birth, ovary of female foetus contains millions of immature oocytes.
b. Ovulation is a process in which follicle ruptures under the effect of luteinizing hormone and oocyte is released from the ovary.
c. Menopause is a natural cessation of menstruation that occurs between the age of 45-50 years.
d & e.
ii. a.
b. (i) 1. No, the incident shown in the given picture is not rational.
2. The picture shows a woman telling an old beggar to leave the area.
3. The beggar must be old, sick, hungry, etc. and should be given proper help. We must help the poor to the best of our abilities.
4. However, in case the beggar is causing disharmony in the area or is an addict he should be immediately handed over to the police or authority in-charge. But ill-treating another person just because they are poor or old is not justified.
(ii) 1. The given figure indicates cybercrime.
2. According to IT ACT – 2000 , the person committing cybercrime has to face imprisonment up to 3 years or a fine up to 5 lakh or both.