life processes (nutrition)

What are Life processes ?

The basic and essential activities performed by a living organism to sustain and maintain life

What is nutrition ?

The process by which a living organism obtained and utilises food is called nutrition

Food gives us energy growth and development

What are the components of food

Carbohydrates

proteins

fats

vitamins and minerals

What is autotrophic nutrition?

Organisms prepare their own food using simple inorganic substances like CO2 and water

Examples include blue green algae and green plants

What is chemosynthesis

It is a type of autotrophic Nutrition

Organisms prepare their own food by utilising chemical energy

Example purple sulphur bacteria

What is photosynthesis?

It is a type of autotrophic Nutrition

Organisms prepared their own food by utilising light energy

Examples include green plants, cyanobacteria and algae

What is heterotrophic nutrition?

A mode of nutrition in which organism depend on other organisms for their food as they do not possess the ability to synthesize their own food

Example all animals

Holozoic nutrition

A type of heterotrophic Nutrition

Animal take in solid food which is broken down inside the body

Examples include amoeba, paramecium and animals

Saprophytic nutrition

It is a type of heterotrophic Nutrition

Organisms feed on dead and Decaying matter

Examples include fungi and mushrooms

Parasite

Form of heterotrophic Nutrition

Parasites live inside or outside another organism the host and derive nutrition from it without killing it

Examples include cuscuta, tics, leech and tapeworms

What is the site of photosynthesis?

Chloroplast are the site of photosynthesis which are green pigmented cell organelles containing chlorophyll

Main events of photosynthesis

Absorption of light by chlorophyll

Conversion of light energy into chemical energy

Splitting of water into hydrogen and oxygen

Reduction of carbon dioxide to carbohydrates

What is stomata and state its functions

Stomata are the tiny pose present on surface of leaves

Functions of stomata:

1. Exchange of gases

2. Removal of excess amount of water by transpiration

How does stomata open and close

It opens when water enters when the guard cells swell

It closes when water leaves ie. on shrinking of guard cells

Features of photosynthesis in desert plants

For reduction of water loss the stomata opens at night for taking in CO2

For conservation of water the stomata is closed during the day

The the co2 is stored in the form of an intermediate and is used for photosynthesis during the day

What is the process of nutrition in amoeba

1. Ingestion: the amoeba surrounds the food particle using pseudopodia and forms a food vacuole

2. Digestion: the enzymes are secreted into the food vaccule breaking the food down into simpler substances

3. Absorption: the digested food is absorbed into the cytoplasm and used for energy, growth and repair

4. Assimilation: the absorbed nutrients are utilised in various life processes

5. Egestion the undigested food is expelled out of the body by rupturing the cell membrane

What is nutrition light in paramecium

Also holozoic nutrition

1. Injection the paramecium uses silia to Sweet food particles through the oral groove where a food vaccule is formed

2. The other steps are similar to amoeba and occur inside food vacuole

What is the alimentary canal

It is a long muscular tube from the mouth to anus

Function of components of mouth (teeth, tongue and saliva)

The teeth crush the food and make it a uniform texture

The salivary glands secrete saliva which contains salivary amylase that breaks down starch into sugars

The tongue mixes food with saliva and helps in following

Function of oesophagus

It connects the mouth to the stomach and no digestion occurs here

The food is pushed down through peristalsis that is the rhythmic contraction of muscles in the Wall of alimentary canal

Stomach function

It is a large g shaped muscular organ

It's a creates HCL, pepsin, and mucus

Functions of HCL

It creates an acidic medium and kills germs

It provides and acidic medium for pepsin to digest proteins

Function of pepsin

To partially digest protein

Function of mucus

It protects the inner lining of the stomach

Role of small intestine (excluding secretions and their functions)

It is the longest part in human body

it is the site of complete digestion and absorption

Receive secretions from liver and pancreas and cities its own intestinal juice

Functions of bile juice

Makes the food alkaline

And emulsifies the fats and breaks the big globules into small droplets to increase surface area

Pancreatic juice

Trypsin digest proteins breaks them down into amino acid

Liepase digest the fats and converts them into simpler form

Role of villi

Will I are finger like projections on the inner wall of small intestine

They increase the surface area for absorption

They have a rich blood supply that helps transport the absorbed nutrients to body cells

Functions of large intestine

It absorbs the water and salts from the undigested food

It prepared waste for excretion

Role of anus

Ejection that is the removal of undigested waste

It is controlled by anal sphincter

Why do herbivores have longer digestive system

Herbivores have longer small intestine and overall digestive system because plant food contains hard to digest cellulose which requires more time for proper breakdown and absorption