WhatsWhat is a Cell / Define cell with four cell organelles?
A cell is the basic structural and functional unit of life.
Two cell organelles are mitochondria and ribosomes.
Mitochondria are responsible for producing energy in the form of ATP.
Ribosomes are responsible for synthesizing proteins.
Why “Lysosomes are called as “Suicidal Bags of the cell”?
Lysosomes are known as suicidal bags of the cell because they contain powerful digestive enzymes that can break down cellular waste and foreign substances by hydrolysis.
If in case a lysosome gets ruptured, its contents can be released into the cytoplasm and cause death of the cell.
This process can lead to the destruction of the cell by its own mechanisms hence they are called as suicidal bags.
What is a cytoplasm?
It is a gel-like substance which is enclosed by the plasma membrane and external to the nucleus of the cell.
The semifluid portion of the cytoplasm in which the cell organelles are suspended is called “Cytosol or Intracellular fluid.”
The cell organelles are embedded in the cytosol.
Cytosol is a clear viscous fluid containing almost 75-90% of water with substances like proteins, fats, lipids, inorganic substances either dissolved or suspended.
What is a nucleus? Give its functions.
The nucleus is a membrane-bound main cell organelle that contains the genetic material of a cell.
The nucleus has several functions, such as:
Storing and protecting the DNA.
Regulating gene expression.
Coordinating cell division.
Producing ribosomes in the nucleolus, which are essential for protein synthesis.
Draw a well labeled diagram of Nucleus.
Why is mitochondria called the powerhouse of the cell?
Mitochondria are called the powerhouse of the cell because they are responsible for producing most of the energy that cells need to function.
Mitochondria convert glucose and oxygen into ATP, which is the main source of chemical energy for cellular processes.
Mitochondria also have their own DNA and can replicate independently of the cell nucleus.
Draw a well labeled diagram of the mitochondria.
Give structure and function of the mitochondria.
Mitochondria contains two membranes made up of lipoproteins.
Outer membrane is intact and covers the entire structure.
Inner membrane is folded and called “Cristae” ; a single is called “Crista”.
The space between two membranes is called intermembrane space.
The center cavity is filled with a fluid called “Mitochondrial Matrix”.
Matrix contains various enzymes needed for cellular respiration.
Mitochondria also contains DNA, which is received from the mother of the individual i.e. Mitochondrial DNA is maternally inherited.
Functions:
ATP synthesis.
Mitochondria are involved in apoptosis, cancer, aging, and pathologies like Parkinson disease and diabetes.
Mitochondria also plays a role in cell signaling.
What are ribosomes giving their functions?
Ribosomes are small organelles that are involved in protein synthesis.
They are composed of two subunits, one large and one small, that contain ribosomal RNA and proteins.
Ribosomes can be found either in the cytoplasm or attached to the endoplasmic reticulum.
They read the messenger RNA that carries the genetic code from the nucleus and translate it into amino acids, the building blocks of proteins.
What is endoplasmic reticulum?
The endoplasmic reticulum is a network of membrane-bound tubules and sacs that extends throughout the cytoplasm of eukaryotic cells.
It has two main types: the rough endoplasmic reticulum, which is studded with ribosomes and involved in protein synthesis and modification; and the smooth endoplasmic reticulum, which lacks ribosomes and is involved in lipid synthesis and detoxification.
The endoplasmic reticulum plays a vital role in various cellular functions, such as protein folding, transport, and quality control; calcium storage and signaling; and lipid metabolism.
What are centrioles?
A centriole is a cylindrical organelle composed mainly of a protein called tubulin.
Centrioles are found in most eukaryotic cells.
A bound pair of centrioles, surrounded by a highly ordered mass of dense material, called the pericentriolar material makes up a structure called a centrosome.
They play a major role in cell division.
What are Peroxisomes?
These are similar to lysosomes but are much smaller in size.
These are smaller vesicles containing many oxidase enzymes capable of causing oxidation of many substances like amino acids, fatty acids, uric acid etc.
The oxidation of fatty acids is a major source for metabolic energy, it produces Hydrogen Peroxide as a byproduct which is harmful to the cell.
