“The human being… the most sophisticated, amazing and wondrous creation in this earth.
If one would take a peek at what’s inside his human body, he’ll be amazed to see hundreds of bones, miles of blood vessels and trillions of cells, all working together so he could be healthy and in perfect shape. Each organ, each body part, each a miracle… Each a piece of evidence of God’s mighty providence.”
This lesson familiarizes you with the principles and stages of human growth, maturation and development. It discusses how humans grow, develop, change and adapt to their environment throughout their life span.
Did you know that there are 26 billion cells in a new born baby and about 50 trillion cells in an adult? Cells are responsible for supplying you with the energy you need, transporting oxygen around your body and moving your body parts. Indeed, every single cell in your body helps you maintain vitality and life.
1. Human Development refers to the biological and psychological development of the human being throughout the lifespan. It consists of the development from infancy, childhood, and adolescence, adulthood to old age.
2. Development refers to the qualitative, progressive series of changes in an orderly and coherent fashion leading to maturation 3. Growth refers to quantitative changes in an individual as he progresses in chronological age.
4. Maturation is the process by which heredity exerts its influence long after birth.
5. Genetics is the science of heredity. It originated with the discovery by Gregor Mendel that hereditary characters are determined by factors transmitted without change and in predictable fashion from one generation to the next.
6. Heredity is the passing on of physical or mental characteristics from parents to offspring through the genes.
7. Gene is a unit of heredity; a segment of the DNA which contains the instructions for the development of a particular inherited characteristic. There are about 30,000 genes that contain chemical instructions. The chemical instructions in the genes program the development of millions of individual parts into a complex body and brain.
8. DNA or deoxyribonucleic acid is a nucleic acid which occurs in combination with protein in the chromosomes, which contains the genetic instructions. It consists of four nitrogenous bases (adenine, guanine, thymine, cytosine), a sugar (2-deoxy-D- ribose), and phosphoric acid, arranged in a regular structure- (two chains twisted round each other in the form of a double helix).
9. Nucleic acids are large molecules produced by living cells which store genetic information, and composed of a chain of nucleotides. Two forms are: deoxyribonucleic acid (DNA) which is found primarily in the nucleus and ribonucleic acid (RNA), found in the nucleus and cytoplasm.
10. Chromosomes are threads within the nucleus of a cell which are the carriers of genetic material, consisting of DNA and various types of protein (histones). They occur in pairs - a normal human body cell has 46 chromosomes: 22 pairs of autosomes together with one matching pair of X chromosomes in females (the 23rd pair- XX) and one mismatching pair, the X and Y sex chromosomes in males (the 23rd pair-XY)
11. Sex chromosome is the 23rd pair of chromosomes represented differently in the sexes, and responsible for the genetic determination of the sex of an individual. There are 1,000 genes in each chromosome.
12. Gamete is a specialized reproductive cell that fuses with another gamete of the opposite sex during fertilization, to form a zygote. Gametes are usually differentiated into male (sperm) and female (egg, ovum).
13. Sexual Reproduction is the act or process of producing offspring through sexual intercourse or artificial insemination.
The Stages of Reproduction: