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Chapter 6. Life Process

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Life process: Those processes of the body which are neccessory to prevent damage and break down and which together perform maintainance job are called life processes. 

These are;

(i) Nutrition

(ii) Respiration

(iii) Transportation

(iv) Excretion

All the organisms require energy to perform various cellular work and to servive. Organisms get this energy by the process of nutrition. 

All the organisms to survive and requires energy to perform various tasks . This energy is derived from the process of nutrition in organisms. This action is a biochemical process called metabolism in the cells, which are rich in oxygen to be rich and oxygen requires the organism from its external environment receives. This process uses oxygen and generates carbon-dioxide (CO₂) to be expelled out is called Respiration. Some single-celled organisms to carry oxygen and carbon-dioxide does not require special organs because their cells are directly exposed to the environment.  But for the exchange of gases in multicellular organisms and their cells to pick up the respiratory tract carries a mechanism (transportation system), which is the circulation system (Circulatory System) is called. When using chemical reactions in carbon source and oxygen for energy recovery occurs such product (porducts) helps bring the body's cells are not only unnecessary but can be harmful. These waste products out of the body, is imperative. Because the process includes all maintenance works of the body is therefore called life process.

1. Nutrition: The process happening in the living organisms in which organisms get energy to change complex materials into simple materials by the biochemical process and utilized them, it is called nutrition. 

Examples of biological process: 

(i) Photosynthesis in plants.

(ii) Digestion in animals 

Bio-chemical process: 

For this life process organisms get complex material from outer enrgy sources and decomposition and formation take place inside the body. By which these are form to maintain and to growth of body. For this there happen a large series of chemical reactions. these are known as bio-chemical process. There is a bio-chemical process called metabolism which takes place in the cells. These celluar process need oxygen to perform this which is obtained from external environment.

The Process of Nutrition

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Get osition of complex materials 

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Changing in simplest useful molecules by bio-chemical process

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Utilizing in the form of energy

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Using in various bio-chemical processes

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Protiens synthesis (Formation of new completes molecules)

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Growth and maintainance of body  

 

Common Chemical Methods for Decomposing of Molecules:

Metabolisms: The decomposing of various molecules in the body are taken place by a chemical proccess is called Metabolism. 

Metabolisms are a bio-chemical proccess which occur in all living organisms to ensure life. 

There are two kinds of metabolisms: 

(i) Catabolism: During this proccess complex organics materials are decomposed into simpler molecules and during cellular respiration this simpler molicules are used to form energy. 

(ii) Anabolism: During this proccess store energy is used by cell for various biochemical proccesses take palce. cells utilised energy for repair, maintance works and also for cell generation. 

Nutrition

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1. Nutrition: The process in living organisms in which an organism converts complex substances into simpler substances through biochemical processes, obtains and uses energy, is called nutrition.

Example of a biochemical process:

(i) The process of photosynthesis in plants

(ii) Digestion in animals

The process of making food in green plants is called photosynthesis. In this process organisms obtain simple substances in the form of carbon dioxide and water from inorganic sources. Such organisms are called autotrophs. Example: Green plants and some bacteria having chlorophyll etc.

Enzymes: To break down complex substances into simpler substances, organisms use certain biocatalysts which are called enzymes.

Types of Nutrition: 

There are two types of nutrition. 

1. Autotrophic Mode of Nutrition: Autotrophic nutrition is the type of nutrition in which organisms synthesize organic matter (food) from inorganic sources on their own. This type of nutrition is done by green plants and autotrophic bacteria.

Examples: All green plants and some bacterias which perform photosynthesis. 

2. Hetrotrophic Mode of Nutrition: The mode of nutrition in which the organism obtains its food from other sources. In this, the organism gets its food from plant sources or from animal sources.

Examples: Algee, Fungus, Man, All Animals, etc.

Types of Hetrotrophic Nutrition: 

There are three types of hetrotrophic nutrition. 

(i) Saprophytic Nutrition: The method of nutrition in which living beings feed themselves from dead and decaying organic matter. Such method of nutrition is  called saprophytic nutrition. This type of nutrition occurs in fungi and most bacterias.

(ii) Parasitic Nutrition: Parasitic nutrition is the method of nutrition in which organisms take their food and habitat (shelter) from another organism and absorb their nutritional source is called parasitic nutrition.

Two types of organisms are involved in this process.

(i) Host: The organism from which parasites absorb food is called host.

(ii) Parasite: Parasites are those organisms that live in the body of the host and absorb their own food and use habitat. For example - Plasmodium found in mosquitoes, tapeworm found in human intestine, roundworm, zoo etc. While in plants, cuscuta.

(iii) Holozoic Nutrition : A method of nutrition in which life energy is obtained by ingestion and digestion of organic matter obtained from plant and animal sources. That is, he takes the food, digests it and then takes it out. For example, humans, amoeba and all animals.

Nutrition in Amoeba: Amoeba also receives nutrition like humans and digests inside the body.

 

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Assignment: 

Q1: What do you mean by residual volume of air? What is its function? 

Q2:.Why is diffusion insufficient to meet the oxygen requirement of the body?

Q3: Explain the events of photosynthesis.

Q4: Give schematic figure showing break down of glucose by various pathways.

Q5: Why is breathing rate much faster in aquatic organism than others?

Q6: Differentiate artery and vein with respect to

i. Wall
ii. Direction of blood flow.
iii. Valves

Q7: Why are capillaries thin walled?

Q8: The wall of ventricle is thicker than atrium. Why?

Q9:. Write the functions of Valve of heart.

Q10:  Why do plants need low energy than animals?

Q11: Name the process of movement of ions into the root cells.

Q12: How does water rise in tall trees?

Q13:  Which process transports soluble products of Photosynthesis?

Q14: In which form photosynthetic is transported in phloem tissue?

Q15: Explain the mechanism of transport of photosynthate?

Q16: Define excretion?

Q16: Name two main constituent of urine.

Q17: Describe the mechanism of urine formation.

Q18: Name three causes that reduce the activity of kidney.

Q19: What are the various ways of excretion by plant?

Q20: Draw the labeled diagram of:
i. Main organs of excretion in human.
ii. Main organs of respiration.
iii. Digestive system.
iv. Human heart.
v. Nutrition in Amoeba.
vi. Stomata.
vii. Glomerulus.