Maharashtra State Board | Aster Classes

50 Marks test

Final Account

Q.1. First Sum.

Q.2. Second Sum.

Dissolution 

Q.3. Third Sum.

Q.4. Fourth Sum.


Q1.तुम्हांला समजलेली कवितेतील सूर्याची भूमिका स्पष्ट करा.

SOLUTION

या कवितेतील सूर्याची भूमिका ही एखाद्या घरातील कुटुंबप्रमुखाप्रमाणे वाटते. जसे एखादा कुटुंबप्रमुख, त्याच्यानंतर त्याच्या कुटुंबाची गैरसोय होऊ नये, म्हणून योग्य ती सोय करून ठेवतो, तसाच सूर्यही त्याच्या अस्तानंतर पृथ्वीच्या प्रकाशमान भविष्याची सोय करू इच्छितो. सूर्य अस्ताला जाताच पृथ्वी अंधारामध्ये बुडून जाणार आहे, तेव्हा पृथ्वीला वाचवण्यासाठी कोणीतरी पुढे यावे असे त्याला वाटते. पृथ्वीच्या चिंतेने त्याचे डोळे पाणावतात. त्याच्यामागे पृथ्वीला आधार देणारे कोणीतरी असावे यासाठी तो संपूर्ण सृष्टीला विनंती करतो; परंतु पृथ्वीच्या रक्षणासाठी कोणीही पुढे येत नाही. हे काम करण्यासाठी जेव्हा इवलीशी पणती स्वत:हून पुढे येते तेव्हा हा सूर्य तिच्या हिमतीचे कौतुक करतो. तिचे नम्र; पण आत्मविश्वासपूर्ण बोलणे ऐकून त्याच्या डोळ्यांत पाणी येते. तो बिनधास्तपणे तिच्यावर पृथ्वीच्या रक्षणाची जबाबदारी सोपवतो. जणू त्याच्यामागे पणती पृथ्वीला सांभाळून घेईल, तिला अंधारात बुडू देणार नाही असा विश्वास त्याच्या मनात निर्माण होतो. त्यामुळे, तो शांतपणे अस्ताकडे झुकतो.

Q2.पणतीच्या उदाहरणातून कवितेत व्यक्त झालेला विचार स्पष्ट करा.

SOLUTION

आपल्या अस्तानंतर अंधकारमय होणाऱ्या पृथ्वीच्या काळजीने सूर्य चिंतित झाला आहे. पृथ्वी अंधारात बुडून जाऊ नये, म्हणून तो या सृष्टीतील घटकांना पृथ्वीला मदत करण्यासाठी पुढे येण्याची विनंती करतो; मात्र कोणीही त्याच्या हाकेला प्रतिसाद देत नाही. त्याचवेळी लहानशी पणती मोठ्या धैर्याने सूर्याचे कार्य जमेल तितके करण्याची जबाबदारी उचलते. सूर्याइतका प्रकाश ती पृथ्वीला देऊ शकत नाही याची तिला पूर्णपणे कल्पना आहे. तरीही ती आपल्या प्रकाशाने शक्य तेवढा अंधार दूर करण्याची तयारी दर्शवते. सूर्याला मदत करण्याची उदात्त भावना या पणतीमध्ये दिसून येते. एखादे कार्य हाती घेताना प्रामाणिकपणा व दृढ इच्छाशक्ती कामी येते. प्रत्येक छोट्यातल्या छोट्या वस्तूमध्ये आंतरिक शक्ती असते. फक्त त्या शक्तीला ओळखून जग सुंदर बनवण्याची इच्छा बाळगणे गरजेचे आहे, हा विचार पणतीसारख्या छोट्या प्रतीकाच्या माध्यमातून येथे व्यक्त झालेला आहे

Q3.सूर्यास्ताच्या दर्शनाने मनात निर्माण होणाऱ्या भावभावना शब्दबद्ध करा.

SOLUTION

सूर्य अस्ताला जाऊ लागला, की कवीमन कविता करू लागते, तर चित्रकाराचा कुंचला अलगद रंगांची उधळण करू लागतो. सूर्यास्ताच्या वेळेचे निसर्गाचे ते रमणीय दृश्य पाहताना मन विचारांनी, आठवणींनी भरून येते. सूर्यास्तासमयी आकाशात दिसणारे रंग डोळ्यांना सुखावणारे असतात.

सूर्योदय – सूर्यास्त जणू मनुष्याच्या जन्म-मृत्यूचे प्रतीक आहेत. मनुष्याचा जन्म म्हणजे सूर्योदय, ऐन तारुण्याचा काळ म्हणजे दिवस आणि म्हातारपण (वार्धक्य) म्हणजे जणू आयुष्याची संध्याकाळ होय. सूर्यास्ताची वेळ मनाला शांतता व समाधानाचा अनुभव देत असते. असा अनुभव माणसाला त्याच्या उतारवयात येत असतो. ऐन तारुण्याचा, उमेदीचा काळ चांगल्या मार्गाने जगल्यास आयुष्याचा शेवटही शांत, समाधानकारक होतो, हेच जणू हा सूर्यास्त आपल्याला सांगत असतो.

दिवसभर कष्ट करणार्या कष्टकऱ्यांसाठी सूर्यास्त विश्रांती घेऊन येतो. आजचा दिवस संपल्याची जाणीव करून देणारा हा क्षण मनात नव्या दिवसाची ओढही जागवतो. गेलेला दिवस भूतकाळात जमा होणार असतो व येणारा दिवस उज्ज्वल भविष्यकाळ घेऊन येत असतो. काहीवेळा अपूर्ण राहिलेले पूर्ण करण्याची आशा मनात निर्माण करून, तर काही वेळा पूर्ण केलेल्या कामांचे समाधान चेहऱ्यावर उमटवून सूर्यास्त आपले विविध रंग आकाशात उधळत असतो. देवळात होणारा घंटानाद, आरतीचे सूर, देव्हाऱ्यातील दिव्याचा मंद प्रकाश सूर्यास्ताचे साैंदर्य वाढवतात. सूर्यास्ताच्या वेळी प्रत्येकाच्या मनात असलेल्या श्रद्धास्थानाप्रती हात जोडले जातात.

Q4.कवितेतील सूर्य आणि पणती या प्रतीकांचा तुम्हांला समजलेला अर्थ सविस्तर लिहा.

SOLUTION

कवी रवींद्रनाथ टागोर यांनी निसर्गातील प्रकाशमान सूर्य आणि मिणमिणता प्रकाश देणारी पणती यांच्या माध्यमातून सजीवसृष्टीतील प्रत्येक वस्तूमध्ये जगाला सुंदर करण्याची क्षमता असते, असा संदेश दिला आहे. 

सूर्यास्तानंतर ही संपूर्ण पृथ्वी अंधकारमय होणार आहे. विश्वाच्या काळजीने सूर्य सर्वांना विनंती करतो, की पृथ्वीला अंधारात बुडण्यापासून वाचवा; पण त्याच्या मदतीला कोणी धावून येत नाही कारण सूर्यासमान क्षमता, सामर्थ्य आपल्यात नाही असे सर्वांना वाटते. अशावेळी पणती पुढे येते, मोठ्या नम्रतेने ती पृथ्वीला सांभाळण्याची जबाबदारी उचलते. भले ती सूर्याइतका प्रकाश पृथ्वीला देऊ शकणार नाही; मात्र पृथ्वीला अंधकारमय होऊ देणार नाही अशी जिद्द मनात ती बाळगते. तिची आंतरिक इच्छाशक्ती श्रेष्ठ आहे आणि त्या आधारेच ती मोठी जबाबदारी उचलते. सूर्यालाही पणतीवर विश्वास आहे. पणतीचे धैर्य अन् नम्र भाव सूर्याला चिंतामुक्त करतो.

आपल्याही आसपास अशा सामर्थ्यशाली व्यक्ती असतात, ज्यांना मदतीची गरज असते. त्यावेळी आपण आपल्या परीने शक्य ती मदत त्यांना करावी. एखाद्या कार्यात आपला खारीचा का होईना, वाटा उचलावा. प्रत्येकामध्ये क्षमता असते; केवळ आपल्यातील क्षमतेला योग्य कार्यात वापरण्याचे ज्ञान, विश्वास व सकारात्मकता आपल्यात असली पाहिजे. जोपर्यंत आपण आपल्या आत लपलेल्या गुणांना जाणून घेणार नाही तोपर्यंत ते कधीच इतरांसमोर येणार नाहीत. या सुप्तगुणांना वाट मोकळी करून द्यावी, कोणालाही कमी लेखू नये कारण या जीवसृष्टीत प्रत्येक वस्तूमध्ये शक्ती आहे अन् प्रत्येक वस्तू आपल्या क्षमतेनुसार जग सुंदर करत असते, असा अर्थ या प्रतीकांतून व्यक्त होतो.

Q5.सूर्य आणि पणती यांच्यातील संवाद स्वत:च्या कल्पनेने लिहा.

SOLUTION

सूर्य:(उदास) अहो, कोणी ऐकतंय का? माझी अस्ताची वेळ झाली आहे. मी अस्ताला गेल्यानंतर या धरतीचे कसे होईल? कोणी येईल का माझ्या मदतीला? या पृथ्वीला अंधारात बुडण्यापासून वाचवा हो!
पणती:हे महान सूर्या! मला तुझ्याशी काहीतरी बोलायचे आहे.
सूर्य:बोल… पणती!
पणती:(नम्रतेने) मी तुझी चिंता दूर करू इच्छिते. मला माहीत आहे, मी तुझ्याइतकी सामर्थ्यवान नाही; पण मला जमेल तसा पृथ्वीवरील अंधकार दूर करण्याचा मी नक्की प्रयत्न करेन.
सूर्य:(आनंदाने) खरंच पणती, तू वाचवशील या पृथ्वीला? तू करशील मला मदत?
पणती:हो! आनंदाने.
सूर्य:तू लहान आहेस; परंतु तुझी जिद्द मोठी आहे. तुझे हे बोल ऐकून माझ्या मनाला मोठा दिलासा मिळाला आहे.
पणती:सूर्यदेवा, तू माझ्यावर विश्वास ठेव. मी नक्कीच तुझा विश्वास सार्थ ठरवेन.
सूर्य:माझा तुझ्यावर पूर्ण विश्वास आहे. तू नक्कीच या धरतीला प्रकाशित करशील. आता मी निश्चिंत मनाने अस्ताला जातो.
पणती:धन्यवाद भास्करा! तू मला माझी क्षमता दाखवण्याची संधी दिलीस.

COMPLETED

Onion cells have no chloroplast. How can we tell they are plants?

SOLUTION

1. The bulb of an onion is a modified form of leaves.

2. While photosynthesis takes place in the leaves (present above the ground) of an onion containing chloroplast, the little glucose that is produced from this process is converted into starch (starch granules) and stored in the bulb.

3. Starch act as reserved food material in plants.

4. Using an iodine solution, we can test for the presence of starch in onion cells. If starch is present, the iodine changes from brown to blue-black or purple. Hence, we can say that though onion cells have no chloroplast they are considered as plants.


Identify cell structure or organelle from its description below.

Manufactures ribosomes

SOLUTION

Manufactures ribosomes – Nucleolus.


Carrys out photosynthesis

SOLUTION

Carrys out photosynthesis – Chloroplast.


Can bud of vesicles, which form the golgi apparatus.

SOLUTION

Endoplasmic Reticulum


Manufactures ATP in animal and plant cells.

SOLUTION

Mitochondria


Selectivelly permeable.

SOLUTION

Plasma membrane.


Chapter 5: Cell Structure and Organization.

Balbharati, solutions, for, Biology, 11th, Standard, Maharashtra State Board, Chapter 5, Cell Structure and Organization, Exercise, [Pages 57 – 58], Label the A, B, C, and D in the above diagram and write the functions of organells A and B,

SOLUTION

A: Mitochondria

B: Endoplasmic Reticulum

C: Golgi complex

D: Amyloplast

Functions of Mitochondria:

i. Shape of the mitochondria may be oval or spherical or like a spiral strip.

ii. It is a double membrane-bound organelle.

iii. Outer membrane is permeable to various metabolites due to the presence of a protein-Porin or Parson’s particles.

iv. The inner membrane is selectively permeable to a few substances only.

v. Both membranes are separated by intermembrane space.

vi. The inner membrane shows several finger-like or plate-like folds called as cristae which bears numerous particle oxysomes and cytochromes/electron carriers.

vii. Inner membrane encloses a cavity called the inner chamber, containing a fluid-matrix.

viii. Matrix contains few coils of circular DNA, RNA, 70S types of ribosomes, lipids, and various enzymes of Krebs’ cycle and other pathways.

Functions of Endoplasmic Reticulum:

i. Smooth endoplasmic reticulum (SER):

a. Depending on cell type, it helps in synthesis of lipids for e.g. Steroid secreting cells of cortical region of adrenal gland, testes and ovaries.

b. Smooth endoplasmic reticulum plays a role in detoxification in the liver and storage of calcium ions (muscle cells).

ii. Rough Endoplasmic Reticulum (RER):

a. Rough ER is primarily involved in protein synthesis. For e.g. Pancreatic cells synthesize the protein insulin in the ER.

b. These proteins are secreted by ribosomes attached to rough ER and are called secretory proteins. These proteins get wrapped in a membrane that buds off from the transitional region of ER. Such membrane-bound proteins depart from ER as transport vesicles.

c. Rough ER is also involved in the formation of membrane for the cell. The ER membrane grows in place by the addition of membrane proteins and phospholipids to its own membrane. Portions of this expanded membrane are transferred to other components of the endomembrane system.


Complete the flow chart.

SOLUTION


Exercise | Q 4. (A) | Page 57

Label the diagram and write down the detail of concept in your word.

Mitochondria

SOLUTION

Mitochondrion is known as the power house of the cell. It plays significant role in aerobic respiration. Mitochondria are absent in prokaryotic cells and red blood corpuscles (RBCs).

The structure of mitochondrion:

1. Shape of the mitochondria may be oval or spherical or like a spiral strip.

2. It is a double membrane-bound organelle.

3. Outer membrane is permeable to various metabolites due to the presence of a protein-Porin or Parson’s particles.

4. The inner membrane is selectively permeable to a few substances only.

5. Both membranes are separated by intermembrane space.

6. The inner membrane shows several fingers like or plate-like folds called as cristae which bears numerous particles exosomes and cytochromes/electron carriers.

7. Inner membrane encloses a cavity called inner chamber, containing a fluid-matrix.

8. Matrix contains few coils of circular DNA, RNA, 70S types of ribosomes, lipids, and various enzymes of Krebs’ cycle and other pathways.


Chloroplast

SOLUTION

Chloroplast plays a significant role in the synthesis of starch in plants.

Structure of chloroplast:

1. In plants, the chloroplast is found mainly in mesophyll of leaf.

2. A chloroplast is lens-shaped but it can also be oval, spherical, discoid, or ribbon-like.

3. A cell may contain a single large chloroplast as in Chlamydomonas or there can be 20 to 40 chloroplasts per cell as seen in mesophyll cells.

4. Chloroplasts contain a green pigment called chlorophyll along with other enzymes that help in the production of sugar by photosynthesis.

5. Inner membrane of double membraned chloroplast is comparatively less permeable.

6. Inside the cavity of inner membrane, there is another set of membranous sacs called thylakoids.

7. Thylakoids are arranged in the form of stacks called grana (singular: granum).

8. The grana are connected to each other by means of membranous tubules called stroma lamellae.

9. Space outside thylakoids is filled with stroma.

10. The stroma and space inside thylakoids contain various enzymes essential for photosynthesis.

11. Stroma of chloroplast contains DNA and ribosomes (70S).


Golgi Apparatus

SOLUTION

Golgi complex or Golgi apparatus or Golgi body act as an assembly, manufacturing cum packaging, and transport unit of the cell.

Structure of the Golgi complex:

1. Golgi complex consists of stacks of membranous sacs called cisternae.

2. Diameter of cisternae varies from 0.5 to 1µm.

3. A Golgi complex may have few to several cisternae depending on its function.

4. The thickness and molecular composition of membranes at one end of the stack of a Golgi sac differ from those at the other end.

5. The Golgi sacs show specific orientation in the cell.

6. Each cisterna has a forming or ‘cis’ face (cis: on the same side) and maturing or ‘trans’ face (trans: the opposite side).

7. Transport vesicles that pinch off from transitional ER merge with cis face of Golgi cisterna and add its contents into the lumen.

Location of Golgi complex:

Golgi bodies are usually located near the endoplasmic reticulum.

Functions of Golgi complex:

1. Golgi body carries out two types of functions, modification of secretions of ER and production of its own secretions.

2. Cisternae contain specific enzymes for specific functions.

3. Refining (modification) of the product takes place in a sequential manner.

4. For example, certain sugar component is added or removed from glycolipids and glycoproteins that are brought from ER, thus forming a variety of products.

5. Golgi bodies also manufacture their own products. Golgi bodies in many plant cells produce noncellulose polysaccharides like pectin.

6. Manufactured or modified, all products of Golgi complex leave cisternae from trans face as transport vesicles.


Reticulum

SOLUTION

structure of Endoplasmic Reticulum:

1. Endoplasmic reticulum is a network present within the cytosol.

2. It is present in all eukaryotic cells except ova and mature red blood corpuscles.

3. Under the electron microscope, it appears like network of membranous tubules and sacs called cisternae.

4. This network of ER divides the cytoplasm in two parts viz. one within the lumen of ER called laminal cytoplasm and non-laminal cytoplasm that lies outside ER.

5. Membrane of ER is continuous with nuclear envelope at one end and extends till cell membrane. It thus acts as intracellular supporting framework and helps in maintaining position of various cell organelles in the cytoplasm.

6. Depending upon the presence or absence of ribosomes, endoplasmic reticulum is called rough endoplasmic reticulum (RER) or smooth endoplasmic reticulum (SER) respectively.

Smooth endoplasmic reticulum (SER):

1. Depending on cell type, it helps in synthesis of lipids for e.g. Steroid secreting cells of cortical region of adrenal gland, testes and ovaries.

2. Smooth endoplasmic reticulum plays a role in detoxification in the liver and storage of calcium ions (muscle cells).

Rough Endoplasmic Reticulum (RER):

1. Rough ER is primarily involved in protein synthesis. For e.g. Pancreatic cells synthesize the protein insulin in the ER.

2. These proteins are secreted by ribosomes attached to rough ER and are called secretory proteins. These proteins get wrapped in membrane that buds off from transitional region of ER. Such membrane bound proteins depart from ER as transport vesicles.

3. Rough ER is also involved in formation of membrane for the cell. The ER membrane grows in place by addition of membrane proteins and phospholipids to its own membrane. Portions of this expanded membrane are transferred to other components of endomembrane system.


Chapter 5: Cell Structure and Organization.

EXERCISE [PAGES 57 – 58]

Balbharati, solutions, for, Biology, 11th, Standard, Maharashtra State Board, Chapter 5, Cell Structure and Organization, Exercise, [Pages 57 – 58], Answer the following questions,

Q.3. Answer the following questions,

Distinguish between smooth and rough endoplasmic reticulum.

SOLUTION

Smooth endoplasmic reticulum (SER):

1. Depending on cell type, it helps in the synthesis of lipids for e.g. Steroid secreting cells of the cortical region of the adrenal gland, testes and ovaries.

2. Smooth endoplasmic reticulum plays a role in detoxification in the liver and storage of calcium ions (muscle cells).

Rough Endoplasmic Reticulum (RER):

1. Rough ER is primarily involved in protein synthesis. For e.g. Pancreatic cells synthesize the protein insulin in the ER.

2. These proteins are secreted by ribosomes attached to rough ER and are called secretory proteins. These proteins get wrapped in a membrane that buds off from the transitional region of ER. Such membrane-bound proteins depart from ER as transport vesicles.

3. Rough ER is also involved in the formation of membrane for the cell. The ER membrane grows in place by the addition of membrane proteins and phospholipids to its own membrane. Portions of this expanded membrane are transferred to other components of the endomembrane system.


Mitochondria are power house of the cell. Give reasons.

SOLUTION

1. Mitochondria possess oxysomes on its inner membrane. These oxysomes take active part in synthesis of ATP molecules.

2. During cellular respiration, ATP molecules are produced and get accumulated in the mitochondria. They play an important role in cellular activities.

3. Only mitochondria can convert pyruvic acid to carbon dioxide and water during cell respiration. Therefore, mitochondria are called ‘power house of the cell’


What are the types of plastids?

SOLUTION

1. Plastids are classified according to the pigments present in it. Three main types of plastids are leucoplasts, chromoplasts and chloroplasts.

2. Leucoplasts do not contain any photosynthetic pigments they are of various shapes and sizes. These are meant for storage of nutrients:

a. Amyloplasts store starch.

b. Elaioplasts store oils.

c. Aleuroplasts store proteins.

3. Chromoplasts contain pigments like carotene and xanthophyll etc.

a. They impart yellow, orange or red colour to flowers and fruits.

b. These plastids are found in the coloured parts of flowers and fruits.

4. Chloroplasts are plastids containing green pigment chlorophyll along with other enzymes that help in production of sugar by photosynthesis. They are present in plants, algae and few protists like Euglena.


Balbharati, solutions, for, Biology, 11th, Standard, Maharashtra State Board, Chapter 5, Cell Structure and Organization, Exercise, [Pages 57], Answer the following question,

Exercise | Q 2. (A) | Page 57

Answer the following question.

Plants have no circulatory system? Then how cells manage intercellular transport?

SOLUTION

1. Plant cells show the presence of plasmodesmata which are cytoplasmic bridges between neighboring cells.

2. This open channel through the cell wall connects the cytoplasm of adjacent plant cells and allows water, small solutes, and some larger molecules to pass between the cells.

In this way, though plants have no circulatory system, plant cells manage intercellular transport.


Is nucleolus covered by membrane?

SOLUTION

A nucleolus is a specialized structure present in the nucleus which is not covered by the membrane.


Fluid mosaic model proposed by Singer and Nicolson replaced Sandwich model proposed by Danielli and Davson? Why?

SOLUTION

1. The Davson–Danielli model of the plasma membrane of a cell, was proposed in 1935 by Hugh Davson and James Danielli.

2. The model describes a phospholipid bilayer that lies between two layers of globular proteins.

3. This model was also known as a ‘lipo-protein sandwich’, as the lipid layer was sandwiched between two protein layers.

4. But through experimental studies membrane proteins were discovered to be insoluble in water (representing hydrophobic surfaces) and varied in size. Such type of proteins would not be able to form an even and continuous layer around the outer surface of a cell membrane.

5. In case of Fluid-mosaic model, the experimental evidence from research supports every major hypothesis proposed by Singer and Nicolson. This hypothesis stated that membrane lipids are arranged in a bilayer; the lipid bilayer is fluid; proteins are suspended individually in the bilayer; and the arrangement of both membrane lipids and proteins is asymmetric.

Therefore, Fluid mosaic model proposed by Singer and Nicolson replaced Sandwich model proposed by Danielli and Davson.


The RBC surface normally shows glycoprotein molecules. When determining blood group do they play any role?

SOLUTION

1. Glycoproteins are protein molecules modified within the Golgi complex by having a short sugar chain (polysaccharide) attached to them.

2. The polysaccharide part of glycoproteins located on the surfaces of red blood cells acts as the antigen responsible for determining the blood group of an individual.

3. Different polysaccharide part of glycoproteins act as different type of antigens that determine the blood groups.

4. Four types of blood groups A, B, AB, and O are recognized on the basis of presence or absence of these antigens.


How cytoplasm differs from nucleoplasm in chemical composition?

SOLUTION

Smooth endoplasmic reticulum (SER):

1. Depending on cell type, it helps in the synthesis of lipids for e.g. Steroid secreting cells of the cortical region of the adrenal gland, testes and ovaries.

2. Smooth endoplasmic reticulum plays a role in detoxification in the liver and storage of calcium ions (muscle cells).

Rough Endoplasmic Reticulum (RER):

1. Rough ER is primarily involved in protein synthesis. For e.g. Pancreatic cells synthesize the protein insulin in the ER.

2. These proteins are secreted by ribosomes attached to rough ER and are called secretory proteins. These proteins get wrapped in a membrane that buds off from the transitional region of ER. Such membrane-bound proteins depart from ER as transport vesicles.

3. Rough ER is also involved in the formation of membrane for the cell. The ER membrane grows in place by the addition of membrane proteins and phospholipids to its own membrane. Portions of this expanded membrane are transferred to other components of the endomembrane system

1. A thick liquid enclosed by a cell membrane which surrounds the central nucleus in eukaryotes or nucleoid region in prokaryotes is known as cytoplasm.

2. The cytoplasm shows the presence of minerals, sugars, amino acids, t-RNA, nucleotides, vitamins, proteins, and enzymes.

3. The liquid or semiliquid substance within the nucleus is called the nucleoplasm.

4. Nucleoplasm shows the presence of various substances like nucleic acid, protein molecules, minerals, and salts.


Chapter 1Living World

EXERCISE [PAGE 5]

Balbharati, solutions, for, Biology, 11th, Standard, Maharashtra State Board, Chapter 1, Living World, Exercise Page 5,

Exercise | Q 1. A. | Page 5

Choose correct option:

Which is not a property of living being?

Metabolism

Decay

Growth

Reproduction

SOLUTION

Decay


A particular plant is strictly seasonal plant. Which one of the following is best suited if it is to be studied in the laboratory?

Herbarium

Museum

Botanical garden

Flower exhibition

SOLUTION

Herbarium


A group of students found two cockroaches in the classroom. They had a debate whether they are alive or dead. Which life property will help them to do so?

Metabolism

Growth

Irritability

Reproduction

SOLUTION

Irritability


Exercise | Q 2 | Page 5

Distinguish between botanical gardens, zoological park and biodiversity park with reference to characteristics.

SOLUTION

Botanical

Gardens         Zoological. Biodiversity


Exercise | Q 3. A. | Page 5

Answer the following questions.

Jijamata Udyan, the famous zoo in Mumbai has acclimatised humbolt penguins. Why should penguins be acclimatised when kept at a place away from their natural habitat?

SOLUTION

Humboldt penguins are kept in temperature monitored chambers. Their food and habitat is maintained as per their natural habitat. This has made them acclimatized to the conditions of the zoo. If such care is not taken, penguins will not be able to survive in Mumbai’s climate having higher temperatures and humidity. These conditions will cause death of penguins, hence they are acclimatized


Riya found peculiar plant on her visit to Himachal Pradesh. What are the ways she can show it to her biology teacher and get information about it?

SOLUTION

Riya can pluck the plant and take it to her teacher after preserving it in the form of herbarium. But this is not advisable as it destroys local biodiversity. Hence she can click pictures of the plant and take it to her teacher. Also by keen observation, the detailed structure of the plant can be noted.


At Andaman, authorities do not allow tourists to collect shells from beaches. Why it must be so?

SOLUTION

1. Seashells are an important part of the coastal ecosystem and are crucial for the survival of various marine creatures.

2. They provide material for building nests of birds and also act as a substratum for attachment of algae, sea grass, sponges and various microbes.

3. Fishes use shells for hiding from predators, whereas hermit crabs use shells as temporary shelters.

4. Removal of seashells from seashores may also indirectly affect the rate of shoreline erosion.

Hence, in an attempt to protect the ecosystem, authorities in Andaman do not allow tourists to collect shells from beaches.


Why do we have green house in botanical gardens?.

SOLUTION

When tourists collect the shells from beaches, it causes loss of biodiversity.

Some shells may contain animal inside.

This should be therefore avoided.

By impact of tourists the natural ecosystem is also disturbed.

There may be illegal trade of the collected shells and specimens.

Therefore, authorities do not allow tourists to do so.


What do you understand from terms like in situ and ex situ conservation?

SOLUTION

1. In situ conservation: It includes conservation of species in their natural habitats. Grazing, cultivation and collection of products from the forests is banned in such areas. Legally protected areas include national parks, wildlife sanctuaries and biosphere reserves.

2. Ex situ conservation: It includes conservation of species outside their natural habitats. Species are conserved in botanical gardens, culture collections and zoological parks.


Exercise | Q 4. A. | Page 5

Write short notes.

Role of human being in biodiversity conservation 

SOLUTION

1. Due to rapid increase in human population and industrialization, humans have over utilized natural resources; leading to degradation of the environment and hence only humans can help conserve the ecosystem.

2. Humans are capable of conserving and improving the quality of nature and thus, can play a major role in biodiversity conservation.

3. In order to conserve biodiversity and its environmental resources, humans must use the resources rationally and avoid excessive degradation of environment.

4. Human beings are stakeholders of the environment and need to come together to overcome pollution and improve the environment quality in order to conserve biodiversity. E.g. Ban or limit on use of harmful products (plastic, chemicals, etc.) that are toxic to various birds, animals, etc.

5. Human beings also play a role in conservation of biodiversity by establishment of various sites for in situ (national parks, wildlife sanctuaries and biosphere reserves) and ex situ (botanical gardens, culture collections and zoological parks) conservation.


Importance of botanical garden.

SOLUTION

1. Local flora is recorded in the botanical gardens.

2. There is collection of monographic works.

3. Living plant material and preserved specimens whlch are needed for studies and research are kept in collection here.

4. Seeds and plants can be supplied from botanical gardens.

5. Greenhouse is maintained for the cultivation of rare and uncommon plants.

6. There is research laboratory associated with some of the botanical gardens.


How can you, as an individual, prevent the loss of Biodiversity?

SOLUTION

As individuals, we can prevent loss of biodiversity in the following ways:

1. Increasing awareness about environmental issues. Making posters that provide more information about biodiversity conservation, to raise public awareness.

2. Increased support and/or active participation in government policies and actions laid down for conservation of biodiversity.

3. Protect various plant and animal species in our surrounding.

4. Set up bird and bat houses wherever possible.

5. Prevent felling of trees especially native plants or trees in a particular area.

6. Reduce, recycle and reuse resources. Especially, reduce pollution and use of plastic bags and other materials that are potential threats for the environment.

7. Use environment friendly products, segregate and dispose garbage correctly.

8. Convince people about the importance of trees and the need to participate in tree plantation campaign.

9. Obey the rules that fall under Biodiversity Act.


All the very best students

VISITORS COUNT

223453
Users Today : 167
Total Users : 223452
Views Today : 303
Total views : 796009

Browse Categories

Archives