Samacheer Kalvi 10th Science Solutions Chapter 12 Pdf

Tamilnadu Board Samacheer Kalvi 10th Science Solutions Chapter 12: Tamilnadu State Board Solution Class 10 Science Chapter 12 – Plant Anatomy and Plant Physiology.

Samacheer Kalvi 10th Science Solutions Chapter 12: Overview

Board	Samacheer Kalvi
Class	10
Subject	Science
Chapter	12
Chapter Name	Plant Anatomy and Plant Physiology

Samacheer Kalvi 10th Science Solutions Chapter 12 Plant Anatomy and Plant Physiology

I.) Choose the correct answer

1.) Casparian strips are present in the _____________ of the root.

a) cortex

b) Pith

c) Pericycle

d) Endodermis

Ans: d) Endodermis

Explanation: Because endodermis is the innermost layer of cortex , having radial and tangential walls called as casparian strips.

2.) The end arch condition is the characteristic feature of

a) Root

b) Stem

c) Leaves

d) Flower

Ans: b) Stem

Explanation: Because, in stem protoxylem lie towards the centre and metaxylem towards the periphery.

3.) The xylem and phloem arranged side by side on same radius is called _________

a) radial

b) Amphivasal

c) Conjoint

d) None of these

Ans: c) Conjoint

Explanation: Because, in conjoint bundles xylem and phloem lie on the same side of the radius.

4.) Which is formed during anaerobic respiration

a) Carbohydrate

b) Ethyl alcohol

c) Acetyl CoA

d) Pyruvate

Ans: b) Ethyl alcohol

Explanation: Because, in anaerobic respiration glucose is converted into ethanolwithout oxygen.

5.) Kreb’s cycle takes place in

a) Chloroplast

b) Mitochondrial matrix

c) Stomata

d) Inner mitochondrial membrane

Ans: b) Mitochondrial matrix

Explanation: Since, Kerbs cycle takes place in mitochondrial matrix.

6.) Oxygen is produced at what point during photosynthesis?

a) When ATP is converted to ADP

b) When CO2 is fixed

c) When H2O is splitted

d) All of these

Ans: b) When CO2 is fixed

II.) Fill in the blanks.

1) The innermost layer of cortex in root is called ____________.

Ans: The innermost layer of cortex in root is called endodermis.

2) Xylem and phloem are arranged in an alternate radii constitute a vascular bundle called ____________.

Ans: Xylem and phloem are arranged in an alternate radii constitute a vascular bundle called conjoint bundles.

3.) Glycolysis takes place in _______________.

Ans: Glycolysis takes place incytoplasm.

4) The source of O2 liberated in photosynthesis is ________________.

Ans: The source of O2 liberated in photosynthesis is splitting of water molecule.

5) ______________ is ATP factory of the cells

Ans: Mitochondria is ATP factory of the cells.

III.) State whether the statements are true or false. Correct the false statement.

1) Phloem tissue is involved in the transport of water in plant.

Ans: False

Correct statement: Phloem tissue is involved in the transport of food and other organic materials in the plant.

2) The waxy protective covering of a plant is called as cuticle.

Ans: True

3) In monocot stem cambium is present in between xylem and phloem.

Ans: False

Correct statement: In monocot stem cambium is absent.

4) Palisade parenchyma cells occur below upper epidermis in dicot root.

Ans: False

Correct statement: Palisade parenchyma is found just below the upper epidermis.

5) Mesophyll contains chlorophyll.

Ans: True

6) Anaerobic respiration produces more ATP than aerobic respiration.

Ans: True

IV.) Match the following

Ans:

Amphirical: Fern
Cambium: Secondary growth
Amphivasal: Dracaena
Xylem: Conduction of water
Phloem: Translation of food

V.) Answer in a sentence

1.) What is collateral vascular bundle?

Ans: Vascular collateral bundles are the bundles of xylem and phloem tissues, where xylem lies towards the center which transport the water and other nutrients to plants and phloem lies towards the periphery which transport food and other organic material to all plant body.

2.) Where does the carbon that is used in photosynthesis come from?

Ans: The green plants are the autotrophic which means they prepare their own food i.e. carbohydrates.

In the process of photosynthesis the green plants prepare their own food by using atmospheric carbon dioxide and sunlight.

3.) What is the common step in aerobic and anaerobic pathway?

Ans: The process of glycolysis is the common step in aerobic and anaerobic pathway which means the breakdown of one molecule of glucose into two molecules of pyruvic acid.

4.) Name the phenomenon by which carbohydrates are oxidized to release ethyl alcohol.

Ans: The process of anaerobic respiration is the process in which carbohydrates are oxidized to alcohol that means glucose is converted into ethanol. Anaerobic respiration is also called as ethanol fermentation by yeast.

VI.) Short answer questions

1) Give an account on vascular bundle of dicot stem.

Ans:

The vascular bundles of dicot stem are conjoint, collateral, and endarch and open on the basis of the position of xylem and phloem. They are surrounded around the pitch in the form of ring.

1.) Conjoint:

Xylem and phloem lies on the same side which transports water and food to all parts of plant body.

2.) Collateral:

Xylem lies towards the center and phloem lies towards the periphery.

3.) Endarch:

Protoxylem lies towards the center and metaxylem lies towards the periphery.

4.) Open:

The cambium is present in between xylem and phloem.

2.) Write a short note on mesophyll.

Ans: The tissues present between upper and lower epidermis is called mesophyll. It is differentiated into palisade parenchyma and spongy parenchyma.

1.) Palisade parenchyma:

It is found just below the upper epidermis. The cells are elongated and having more no. of chloroplasts and taking part in the process of photosynthesis.

2.) Spongy parenchyma:

It is found below the palisade parenchyma tissue. And Cells are mostly spherical or oval and irregularly arranged. It helps in gaseous exchange.

3) Draw and label the structure of oxysomes.

Ans:

4) Name the three basic tissues system in flowering plants.

Ans: Sachs classified tissue system in plants into three types which are discussed below.

1.) Dermal or epidermal tissue system:

It has the components as epidermis and periderm and having function to protect and prevent the loss of water.

2.) Ground tissue system:

It has components as parenchyma tissue, collenchyma tissue and sclerenchyma tissue and its helps in photosynthesis, food storage, regeneration, support and also in protection.

3.) Vascular tissue system:

It has the components as vascular tissues i.e. xylem and phloem tissues whose function is transport of water and minerals, transport of food to the all body parts of the plants.

4.) What is photosynthesis and where in a cell does it occur?

Ans:

Photosynthesis is the natural process by which autotrophic organisms i.e. organisms preparing their own food or feeding their own nutrition like green plants, algae and chlorophyll containing bacteria uses the energy from the sunlight and atmospheric carbon dioxide to produce their own food.

In photosynthesis, the carbon dioxide and water combines in the presence of sunlight and chlorophyll and forms the carbohydrates with the release of oxygen as byproduct in the atmosphere which is the life of living organisms.

Photosynthesis occurs in all green parts of plants mostly in green leaves.

5.) What is respiratory quotient?

Ans:

Respiratory quotient is the ratio of volume of carbon dioxide liberated and the volume of oxygen consumed during respiration.

It is defined as,

RQ= Volume of CO₂ liberated/ Volume of O₂ consumed

6.) Why should the light dependent reaction occur before the light independent reaction?

Ans:

The light dependent reaction occurs first than the light independent reaction because the products formed in light reaction are used to form the products in dark reaction.

That means, in light reaction the photosynthetic pigments absorbs the light and convert it into chemical energy ATP and NADPH₂.

And during dark reaction, the CO₂ is reduced into carbohydrates of light generated ATP and NADPH₂.

7.) Write the reaction for photosynthesis?

Ans:

VII.) Long answer questions

1) Differentiate the following

a) Monocot root and Dicot root

Ans:

Dicot root:

The no. of xylem in dicot root is tetrarch.
The cambium is present in dicot root during secondary growth only.
Secondary growth is present in dicot root.
Pitch is absent in dicot root.
Conjunctive tissues are parenchyma and the example of dicot root is bean.

Monocot root:

The no.of xylem in monocot is polyarch.
Cambium and secondary growth is absent in monocot root.
Pitch is present in monocot root.
The conjunctive tissues are sclerenchyma and example of monocot is maize.

b) Aerobic and Anaerobic respiration

Ans:

Aerobic respiration:

It is the cellular respiration in which organic food is completely oxidized by using oxygen to form carbon dioxide, water and energy.
It involves three steps to complete that are glycolysis, Krebs cycle, electron transport chain.

Anaerobic respiration:

It is the process in which glucose is converted into ethanol in the absence of oxygen.
The end products formed are lactic acid, ethanol and ATP.
It involves the two steps that are glycolysis and ethanol fermentation by yeast.

2.) Describe and name three stages of cellular respiration that aerobic organisms use to obtain energy from glucose.

Ans:

Aerobic respiration is the cellular respiration in which organic food is completely oxidised by using oxygen into carbon dioxide, water and energy.

It occurs in most of the plants and animals.

C₆H₁₂O₆ + 6O₂→ 6CO₂ + 6H₂O + ATP

The aerobic respiration involves three steps which are described as below.

1.) Glycolysis:

It is the breakdown of one molecule of glucose into two molecules of pyruvic acid. It takes place in cytoplasm of the cell and it is common in both aerobic and anaerobic respiration.

2.) Krebs cycle:

It occurs in the mitochondria matrix.

At the end of glycolysis two molecules of pyruvic acid enters into mitochondria. The oxidation of pyruvic acid into CO₂ and water takes place in this cycle.

3.) Electron transport chain:

It occurs through the process of electron carrier complex called electron transport chain which is located on the inner membrane of mitochondria.

NADH₂ and FADH₂ molecules formed in the process of glycolysis and Krebs cycle are oxidized to NAD⁺and FAD⁺ by releasing energy through the electron.

This electrons moves through the system and releases energy which is get absorbed by ADP to synthesise ATP, which is also called as oxidative phosphorylation.

And O₂, which is the accepter of electron is reduced into water.

3) How does the light dependent reaction differ from the light independent reaction? What are the end product and reactants in each? Where does each reaction occur within the chloroplast?

Ans:

Light reaction:

Light reaction is also called as Hill reaction and it occurs in the presence of light.
It occurs in the thylakoid membrane of the chloroplasts.
The photosynthetic pigments absorbs the light energy and convert it into chemical energy ATP and NADPH2.

Dark reaction:

Dark reaction is also called as Biosynthetic phase which occurs in the absence of light.
It occurs in the stroma.
In this reaction CO₂ is reduced into carbohydrates with the help of light generated ATP and NADPH₂.
It is also called as Calvin cycle.

The reactants in the light dependent reaction are photosynthetic pigments and end products are ATP and NADPH₂.

The reactants in light independent reaction are carbon dioxide, which is reduced into carbohydrates with the help of light generated ATP and NADPH₂.

Light reaction occurs in the grana of the chloroplasts while dark reaction occurs in the stoma of the chloroplasts.

VIII.) Higher Order Thinking Skills (HOTS)

1) The reactions of photosynthesis make up a biochemical pathway.

Ans:

A. What are the end product of light and dark reaction of photosynthesis?

The light reaction occurs in the presence of light in the grana of chloroplasts.

The photosynthetic pigments absorbs the light energy and convert it into ATP and NADPH₂.

The dark reaction occurs in the absence of light in the stoma of chloroplasts.

In this reaction, CO₂ is reduced into carbohydrates with the help of light generated ATP and NADPH₂.

B. Explain how the biochemical pathway of photosynthesis recycles many of its own reactions and identify the recycled reactants.

In light reaction, the photosynthetic pigments absorbs light energy and convert it to ATP and NADPH₂.

Then in dark reaction, CO₂ is reduced into carbohydrates with the help of light generated ATP and NADPH₂. Again this cycle produces inorganic phosphate which is used in light reaction to produce again ATP and NADPH₂.

2) Where do the light dependent reaction and the Calvin cycle occur in the chloroplast?

Ans:

The light dependent reaction takes place in the presence of light energy in the thylakoid membranes i.e. grana of the chloroplasts.
Dark reaction or biosynthetic pathway or Calvin cycle occurs in the stoma of the chloroplasts.