Nutrition in unicellular and multicellular animals Prepared by Mrs Farkhunda Naz DA Degree College Ph VI Biology Deptt
Contents of Presentation • Nutrition • Heterotrophic Nutrition in Animals • Types of heterotrophic Nutrition • Types of animals on the basis of food • Holozoic Nutrition • Types of Digestion
Contents of Presentation • Nutrition in different animals • Nutrition in Amoeba • Nutrition in Hydra • Nutrition in Planaria • Nutrition in Cockroach
What is Nutrition? • Nutrition (also called nourishment or aliment) is the provision, to cellsandorganisms, of the materials necessary (in the form of food) to support life. Many common health problems can be prevented or alleviated with a healthy diet.
Heterotrophic Nutrition in Animals • .Heterotrophic nutrition is nutrition obtained by digesting organic compounds. • Animals, fungi, many prokaryotes and protoctists are unable to synthesize organic compounds to use as food. They are called heterotrophs.
The four main types of heterotrophic nutrition are: • Holozoic nutrition: Complex food is taken into a specialist digestive system and broken down into small pieces to be absorbed. • Saprotrophic: Organisms feed on dead organic remains of other organisms. • Parasitism: Organisms obtain food from other living organisms (the host), with the host receiving no benefit from the parasite. • Mutualism: A symbiotic relationship between organisms, with each contributing and benefiting from each other.
Types of Animals on the basis of food • Detritivores • Predators • Herbivores • Carnivores • Omnivores • Microphagus feeders • Macrophagus feeder • Fluid feeders • Filter feeders
Holozoic Nutrition • Holozoic nutrition (Gr. holo, whole + zoikos, of animals) is a method of nutrition that involves the ingestion of liquid or solid organic material, digestion, absorption and assimilation of it to utilize it. This method suggests phagocytosis where the cell membrane completely surrounds afood particle.
Five steps of Holozoic Nutrition • Ingestion • Digestion • Absorption • Assimilation • Egestion
Types of Digestion • Extracellular Digestion • Intracellular Digestion • Mechanical Digestion • Chemical Digestion
Nutrition in Amoeba • Unicellular • Freshwater organism • Microphagus Feeder • Intracellular digestion • Ingestion by pseudopodia • Two pseudopodia at the same time formed cup like structure around the food. • Food vacuole formed
Process of Digestion • Lysosomes attached to food vacuole • Lysosomes secrete enzymes like proteases, amylases and lipases in food vacuole • Food vacuole decreases in size due to water loss • It increases acidity and PH becomes 5.6 and Then 7.3 • Fine canals produced from digestive vacuole • Absorption of food takes place by micropinocytosis • Food is circulated throughout the cytoplasm by cyclosis.
Nutrition in Hydra • Multicellular • Diploblastic • Belongs to phylum Cnidarians' • Macrophagus feeder • Aquatic animal • At the anterior end mouth surrounded with tentacles which are used to capture the pray • In tentacles special cells Nematocysts are present • Nematocysts contains poison which paralyze the pray.
Process of Digestion • The mouth of hydra opens into a cavity called gastrocoel or enteron. • The endoderm contains two types of cells, glandular and flagellated. • Glandular cells secrete proteolytic enzymes , which are helpful in digestion • The flagellated cells and contraction of body wall also help in digestion • Hydra cannot digest starch. • The digestion is extracellular as well as intracellular
Nutrition in Planaria • Flatworm • Belongs to phylum Platyhelminthes • Carnivores • Tube like alimentary canal is present • It has three parts: mouth, pharynx and intestine • When it takes food from outside, the pharynx comes out from the mouth • Internally the pharynx opens into the intestine, which divides into three branches
Process of Digestion • The branching system is formed for digestion, absorption and distribution of food • This system is called Gastro-Vascular system • The food is taken in through the mouth which comes into the pharynx and then intestine • The enzyme act upon the food in the intestine • The digested food is absorbed by the branches of intestine, which is distributed throughout the body by diffusion • Digestion is both intracellular and extracellular
Nutrition in Cockroach • Insect • Omnivores • It uses antennae in the search of food • Tube like alimentary canal present having three parts • Fore gut or Stomodaeum • Mid gut or Mesenteron • Hind gut or Proctodaeum
Process of Digestion • Fore gut consists of mouth, buccal cavity, pharynx, oesophagus, crop and gizzard • Food ingest through mouth, then comes into the pharynx , pass through the oesophagus and then stores in the crop • Gizzard has thick lining for the grinding of food • The upper outer surface of mesenteron 6-8 club shaped hepatic cecae arises which secrete digestive enzymes • After digestion food is absorbed in mid gut
Process of Digestion • Hind gut consists of three parts: • Short tubular Ileum • A long coiled colon • A broad rectum opening out through the anus • The rectum absorbs and conserve s the much needed water from the undigested food before expelling out the faeces.
Quiz paper • Q1: The nutrition which is obtained by digesting organic compounds is called as • Holozoic • Heterotrophic • Autographs • Saprotrophs • Q2: There are five steps of holozoic nutrition: Ingestion, digestion, absorption , assimilation and egestion. • True • False • Q3: The digestion in hydra is _______________ as well as ___ • Q4: How many different parts of tube like alimentary canal are present in cockroach? • Q5: The process of ingestion takes place by _______________ in amoeba.
References • Internet • Text book • www.Google.com • www.Youtube.com