A BRIEF OVERVIEW OF THE PREVIOUS CLASS AND Q&A SESSION (05:01 PM)

MINERALS (05:05 PM)

• Minerals are inorganic nutrients that are needed in small amounts and play a key role in ensuring the health and well-being of an organism. 

MACRO-MINERALS 

• Calcium- The Source of calcium is Milk and Milk Products. Deficiency of calcium leads to weaker bones and bad muscle movement. The deficiency causes Rickets. 
• Sodium- The source of sodium is a common table salt. A deficiency of sodium leads to fluid imbalance and dehydration. 
• Potassium- Sources are most fruits and vegetables and its deficiency causes Muscle weakness. 
• Phosphorus-  Sources are Milk, pulses, and deficiency causes weaker teeth and bones.
• Magnesium- Sources would be Nuts and seeds and its deficiency causes poor muscle coordination.
• Chlorine- The source would be common table salt and its deficiency causes fluid imbalance and dehydration. 
• Sulphur- Sources are meat, egg, and fish. A deficiency of sulfur can lead to protein deficiency in the body. 

MICRO-MINERALS 

• Iron- Iron makes up the structure of Haemoglobin. Sources are Meat, pumpkins, and Spinach, and its deficiency causes iron-deficiency anaemia. 
• Fluorine- The source of Fluorine is drinking water and the deficiency of fluorine can lead to Tooth Decay or caries. [* The name of the disease is Fluorisis. The colour of the teeth changes. If drinking water contains a high amount of fluorine then it results in the weakening of bones].
• Copper- The sources would be pulses, Nuts, and seeds and its deficiency can cause a low White blood cell count.
• Iodine- In common salt (NaCl) Iodine is added, which is called Fortification. The source is iodized table salt. A deficiency of Iodine causes Goitre. 
• [* Note- Food fortification means adding some nutrients to the food. All natural salts do not contain Iodine. Iodine is part of Thyroid harmone]
• [* Note- Sodium and chlorine are important for fluid balance. Low salt intake will lead to low water intake. Less water will lead to low blood pressure. Natural salt contains low sodium, thus it is suggested to consume natural salt and iodized salt alternatively] 
• Zinc- The sources are different kinds of beans and eggs. Its deficiency causes Diarrhea. 

CELL BIOLOGY (05:39 PM)

• The cell is the basic structural and functional unit of all known forms of life. 
• Types of organisms based on the number of cells 
• Unicellular organisms- Every function has to be performed by one cell. They contain only a single cell that performs all the life processes. Examples- Amoeba, Euglena, Paramecium.  
• Multicellular organisms- They consist of more than one cell. The different cells are specialized for different functions all of which coordinate to make life possible for an organism. Specialization of work/ division of labour can be possible. Examples- Plants, Animals, and Humans.
• Genetic material 
• The hereditary material present in all cells is DNA. It is passed from one generation to another through genes.
• Cell organelle
• Cell organelles are defined as specialized subunits present within a cell that carry out a specific function and are usually enclosed within its membrane
• Types of organisms Based on the organization within the cell 
• Prokaryotes-
• These will always be unicellular organisms that lack a membrane-bound Nucleus and cell organelle
• The genetic material i.e. DNA is circular and is present in the Nucleoid region. Examples- Bacteria, Cyanobacteria or Blue-Green Algae. 
• Eukaryotes-
• They can be Unicellular or Multicellular which have a membrane-bound Nucleus and Cell organelle. 
• The genetic material i.e. DNA is linear and is organized in the form of rod-like structures called chromosomes. Examples- Amoeba, Fungi, Plants, Animals, etc
• 

STRUCTURE OF CELL (06:12 PM)

• Cell membrane
• The cell membrane or plasma membrane is the biological membrane that separates the interior of all the cells from the outside environment.
• It is made up of Phospo-lipids. 
• Cell wall 
• It is the structural layer surrounding the cell membrane in certain types of cells. 
• It provides additional support and protection. 
• The plant's cell wall is made up of cellulose, the Bacterial cell wall is made up of Peptidoglycan, and the Fungal cell wall is made up of Chitin. 
• Cell Nucleus 
• It is the controlling centre of all the activities of the cell. 
• It contains the genetic material of the cell. 
• It is generally spherical in shape and located in the centre of the cell. 
• It is also called the Brain of the cell
• Cytoplasm 
• It consists of all the components of the cell enclosed within the cell membrane other than the Nucleus. 
• Protoplasm
• It is the living part of the cell which includes the nucleus and the cytoplasm
• Mitochondria
• Mitochondria is the site for energy production in the cell and is thus called the "Powerhouse of the cell"
• It has its own DNA. 
• Ribosomes
• They are the sites for protein synthesis in the cell.
• They can be present freely or attached to the Endoplasmic reticulum
• Endoplasmic Reticulum 
• It is a large network of tubes that act as channels of transport within the cell 
• Rough Endoplasmic Reticulum- It contains attached ribosomes and is involved in Protein synthesis. 
• Smooth Endoplasmic reticulum- It does not contain attached ribosomes and is involved in the manufacture of fats. 
• Golgi Body 
• It packages and dispatches material to various targets inside and outside the cell. 
• Lysosomes 
• It contains powerful digestive enzymes which can break down any foreign material as well as worn-out cell organelle. 
• It can digest the whole damaged cell making it the "suicide bag of the cell". 
• Vacuoles
• These are the storage structures of the cell. 
• They can be present in the form of a single large structure in plant cells and multiple small structures in animal cells. 
• Plastids
• These are pigment-containing structures present only in plant cells. 
• They have their own DNA and are of three types- Chloroplast for green colour parts, Chromoplast for other different colours, and Leucoplast for white to colourless. 

PLANT CELL V/S ANIMAL CELL (06:54 PM)

	Plant cell	Animal cell
Cell wall	Presence of cell wall	Absence of cell wall
Vacuoles	One large vacuole	Small in size, but multiple vacuoles
Plastids	Plastids are present	No plastids
Nucleus	Peripheral Nucleus	Central Nucleus
Storage of glucose	Starch	Glycogen

CLASSIFICATION OF ORGANISMS (07:00 PM)

• CLASSIFICATION OF ORGANISM- 5 KINGDOM

  MONERA Prokaryote Unicellular Example- Bacteria, Cyanobacteria or Blue-green Algae PROTISTA Eukaryotes Multicellular Examples- Amoeba, paramecium, Euglena FUNGI Eukaryotes Unicellular as well as multicellular Example- Yeast, Mushroom PLANTAE Eukaryotes Multicellular Example- Algae.  ANIMALIA Eukaryotes Multicellular Example- Hydra, Human beings.

VIRUS (07:09 PM)

• Viruses have their own genetic material (DNA or RNA) and their own proteins but they lack the enzymes needed for energy production.
• They can grow and replicate only inside the living cells of another organism. They can infect animals, Plants, or even micro-organisms like Bacteria. 
• 

DIGESTIVE SYSTEM (07:16 PM)

• It is the system that breaks down food into simpler parts. 
• 

• Digestive system

  Organ Enzymes  Effect on Nutrient Mouth Salivary glands- Saliva Enzyme- Amylase Breakdown of carbohydrate (First compound which is broken down) Oesophagus or Food pipe   No breakdown will take place Stomach HCL and protease enzyme (gastric juice) Liquid secretion is called Gastric juice Breaking down of Protein Small intestine (The longest part of the digestive system) Intestinal juice-  Peptidase for proteins Sucrase, maltase, and lactase for carbohydrates Protein and Carbohydrates are further broken down Liver Bile (It does not contain fat digestion enzyme) Bile is produced by the liver and stored in the gallbladder Enzymes come from the pancreas.  Pancreatic juice contains protease for protein, Lipase for lipids or fat, and Amylase for carbohydrates. Helps in fat digestion, carbohydrates, and protein digestion

• Stomach-
• It is closed on both ends with the Spinchter muscle
• It is tilted. 
• If the acid goes backwards it leads to acidity. When the food is in excess then in this case stomach does not seal properly. Secondly, one should not lie down after having food. In this position, the sphincter does not close properly and reflux may happen
• Small intestine
• It has a rich blood supply
• Nutrients are absorbed into the blood. 
• Large Intestine
• It receives all the extra water and undigested waste. 
• [* High fibre content/ fibrous content- This is mainly cellulose and not digested by humans. The purpose is that it creates volume or bulk of the food and helps in the digestion of food. It helps in the easy removal of the stool. ]

RESPIRATORY SYSTEM (07:36 PM)

• Respiration means energy production. Mitochondria is responsible for cellular respiration. The second stage is gaseous exchange. 
• 1. Cellular respiration 
• All the cells of the body, individually produce their own energy. For producing energy it needs Glucose. 
• a) Aerobic respiration-
• Glucose + O2===> Co2+ H2O+ Energy
• Muscle cells can produce energy when there is insufficient oxygen supply. 
• Glucose==> lactic acid (Leading to Muscle cramp) + Energy (Muscle cells)
• b) Anaerobic respiration 
• Glucose==> Ethanol + Co2+ Energy
• It happens in Bacteria, Yeast. 
• This process is also called fermentation
• 2. Gaseous Exchange 
• From the Nasal cavity, Air enters. Then it goes through Pharynx. After this, it passes through Larynx. 
• After the larynx, it goes through Trachea. 
• Trachea divides into two Bronchi. 
• Bronchi divides into Bronchioles. 
• Alveoli have a rich supply of blood. At Alveoli, gaseous exchange occurs
• [* Co2 is coming in dissolved form. Haemoglobin has a very high affinity for oxygen. When Air comes it gets attached to Oxygen and carries it]
• Homework 
• NCERT Class VII- chapter 2
• NCERT Class IX- Chapter 5

The topic for the next class:- Endocrine system, Circulatory system, and Health.