Article # 4
How the Plants prepare its food
Look,The plants absorb water and inorganic minerals from soil through roots. Carbon dioxide is obtained from the air
and Oxygen is released through tiny pores in leaves called stomata. Energy is obtained from sunlight by chlorophyll (a green color pigment of leaf). In this process solar energy is converted into chemical energy. The chemical energy is stored in the form of carbohydrate (glucose) and then starch which is used as a fuel by the plant for its growth throughout its life. The process is light dependent, therefore it is called photosynthesis. No sunlight means no plants and no oxygen and food and hence no life.
The plants give us oxygen by which we sustain our lives and we exhale carbon dioxide necessary for plant life. We
depend on plants and plants on us.
Q. Is it coincident or predestined?
Reproduction in plants
Look, how the plants reproduce and grow. Some plants grow from vegetative parts like leaves, roots, buds and stems capable of giving rise to new plants and that is called asexual reproduction.
Some plants grow from reproductive parts of flowers and that is called sexual reproduction. A flower may either possess male parts or female parts or both. Flowers perform reproductive functions in plants. When the male parts (pollen grains) from stamen come in contact with the female part of the flower ovule through pollen tube, they fertilize and fruit formation starts. Ovary develops into fruit, while ovule develops into seed enclosed in the fruit. Plants like strawberries, blackberries and peach trees. Pears, Plumps, Apricots and Citrus etc. grow from seeds.
Seeds are the products of sexual reproduction. They contain DNA (deoxyribonucleic acid). DNA contains the genetic information. It comes from male parts (pollen grain) and female parts (ovule) of the flowers. When the seed is planted in the ground, the DNA in the nucleus tells the seed cells how to grow into a plant.
Q. Is it not predestint?
Note, there are more than 380,000+ known species of plants out of which some 260,000+ are seed or flowering plants. Each one is different from the other in all respects, because of different sequences of nucleotides in their DNA. The DNA in the cells of plants and animals are same in structure, but different in sequence of arrangement of four chemical molecules Nucleotides i.e., Adenine, Thymine, Cytosine and Guanine from which they are made. All are made of atomic particles. All living things have DNA in their cells.
Q. How does DNA contain all the information and instructions needed for a plant to build, survive and reproduce?
Q. How does DNA produce protein via genes to carry these functions?
Q. How does the DNA (group of nucleotides) direct the cells to function?
Q. How the sequences of nucleotides (group of atoms) bring differences?
Q. How does this intricate system work?
Origin of life from atomic particles
All forms of life are merely a collection of different atomic particles. According to scientific research, the earth was created some 4.57 billion years ago and life appeared on it about 3.0 billion ago, therefore no one knows the exact steps in the formation of life on earth. As the origin of life is a very complicated topic and there are plenty of ideas, assumptions, hypothesis, and theories about it, but I will consider only the Oparin’s hypothesis, relating to atomic particles and which is the main concern of my topic.
Alexander Oparin’s hypothesis
It says that Earth’s early atmosphere was very reactive, which provided the energy needed for the simple molecules to react and formed more complex compounds gradually through a series of reactions.
The Miller–Urey experiment tested the Oparin hypothesis
They used hydrogen, methane, ammonia, and water in the experiment, as they thought these gasses were present at
the time of early earth atmosphere. They heated the liquid water in the flask and passed the water vapors through an electric spark chamber to give the early earth atmospheric conditions and then condensed in the apparatus. At the end of a few days of continuous operation Miller and Urey observed organic molecules Amino acids in it. The experiment provided that life originated spontaneously on earth from simple molecules to complex molecules.
Amino acids:
It is the basic building blocks of living organisms. Each amino acid is composed of a central carbon (alpha carbon)
bonded to hydrogen, carboxyl group, amino group and a unique side chain or R-group. Amino acids bond each other to make long chains. It is the R- group that differs the 20 amino acids from each other. Life on earth is complex and varied, but every living organism on the planet earth builds its proteins from the same set of 20 amino acids. The 20 different R groups give amino acids individual characteristics. The number and sequence of amino acids determines which protein results. Protein plays a crucial role in almost all biological processes. Each protein has its own unique characteristics.
Q. What source produced amino acid and how did the R- group bring such a big change?
In all living forms of life, these amino acids are organized into proteins, and the construction of these proteins is
mediated by nucleic acids.
Q. How nucleic acid was formed as there was no nucleic acid in the experiment of Miller and Urey?
Q. Is it itself made or made by some source ?
Note: Atoms combine to form molecules (amino acid); amino acids combine to form proteins and proteins make cells, Cells combine together to form body tissues, such as muscle, skin, or bone tissue. Tissues make up the organs in the body, such as your heart, liver, or lungs etc. Each organ has its own job to do, but all organs work together to maintain the body.
Q. Did it happen randomly or was it meant to happen?
Cell The cell is the basic, structural, functional and biological unit of living organism. Cells are made of water, fats,
Proteins, Carbohydrates (sugars), vitamins and nucleic acids. All are made of atomic particles (Hydrogen, Carbon, Nitrogen and Oxygen. Cells carry out specialized functions like:
Red blood cells carry oxygen.
Nerve cells carry and receive impulses to/from different parts of the body.
Muscle cells bring parts of the body closer.
Brain cells send and receive signals throughout your body etc.
Q. How did the cell and cell wall develop?
Q. How did the division and multiplication of the cell take place?
Q. How do the cells know to make an eye or a nose, hand or a foot?
DNA (deoxyribonucleic acid)
The chromosomes are inside the nucleus of all living cells. Chromosomes are made of long molecules of (DNA) coiled
many times around the proteins and store all types of the genetic information, instructions for the development, growth, reproduction and functioning of an organism via genes by protein synthesis.
Structure of DNA
DNA is made up of molecules called nucleotides. The nucleotides in DNA consist of three components: a phosphate group, a sugar group and four nitrogenous bases (Adenine, Thymine, Guanine and Cytosine. (All made of atomic particles like; O, H, N, C and P atoms). DNA looks like a twisted ladder (double helix). Each “rung” of the ladder is a nitrogenous base. The phosphate and sugar molecules form the sides (strands), while the nitrogenous bases form the rungs. The bases on one strand pairs with the bases on another strand: Adenine pairs with Thymine and are held together with 2 hydrogen bonding & Guanine pairs with Cytosine and held together with 3 hydrogen bonding. Deoxyribose sugar is a 5 carbon structure. Base is connected with carbon 1 of the sugar, phosphate group is connected with carbon 5 of the sugar and the phosphate group of another nucleotide is connected with the carbon 3 as shown in the figure. The 5 end will have a free phosphate group and the 3 end will have a free OH group. Both strands run from 5 ends to 3 end directions, anti parallel and opposite to each other. The nucleotides are connected to one another by phosphodiester linkage between the sugar of one nucleotide and the phosphate of the other nucleotide, resulting in the sugar phosphate backbone.
Look, the sequence of these bases creates a unique genetic code for building and maintaining an organism like the order of alphabets of languages make different words and different words make different sentences.
How does the genetic information lie in the sequence of nitrogenous bases?
How is DNA a complete blueprint of the organism?
How, the instruction from DNA allows cells to do life function and reproduction process?
How does DNA store genetic information?
Gene
A gene is a segment of DNA. The sequence of nitrogenous bases in a DNA forms genes. The sequence of nitrogenous
bases in the gene decides which amino acids and hence which specific proteins are formed. Each gene creates a specific protein performing a different function.
How, the arrangement of nucleotides in the DNA structure stores all the genetic information of life?
How, the DNA instruct cells to make different organs and do lives function?
How, the different sequence of nucleotides in DNA molecules makes species each different from other in all respects? How, 25,000 genes in DNA molecules store all types of genetic information?
Q. Is it not all planned?
Look, the role of Sex Chromosome All cells in a human body have 23 pairs of chromosomes or 46 numbers of chromosomes, half from Mom and half from Dad. Sperm and egg cells contain 23 numbers of chromosomes,half the number of chromosomes found in a typical human cell, which is 46. Sperms are produced in the testes of male and eggs (ova) in the ovary of females.
Sperm cells have either one X or one Y chromosome. An egg cell always has one X chromosome. The sex of an individual is determined by a pair of sex chromosomes. During fertilization if the X chromosome of sperm fertilizes the X chromosome of egg, the result will be a female baby and if Y chromosome of sperm fertilizes the X chromosome of egg the result will be male baby. The fertilized ovum will have two sex chromosomes XX or XY.
Note: There are 50% sperms with Y chromosomes and 50% sperms with X chromosomes in male.
Q. Why is there an exception in egg and sperm cells ? Think, think and think on this point?
Q. Is it a coincidence or predestined?