9th 10th
Transport Of The Materials Across The Cells Lesson-12.2
In the living organisms, each cell is bounded by cell membrane. The cell membranes are able to regulate the movement of materials across them. The cells constantly exchange materials with their environment through the cell membranes. But the movement of materials, in and out of the cells, across the cell membranes is not an uncontrolled [...]
Genetic Engineering And Biotechnology Lesson 20.1
Genetic engineering is a technique used to transfer useful genes from one organism to another for attaining a specific benefit for mankind. You have already studied it in detail in chapter 17. 20.1.1 Transgenic bacteria and the preparation of insulin One of the proteins formed by the process of genetic engineering is insulin. Insulin is [...]
Man and biology (10th-biology-chapter-20)
In this chapter you will learn: 1. Definition and process of biotechnology and genetic engineering 2. Role of biology in the economic development of various aspects of human life. 3. Biological control of pests. 4. Definition, source and control of pollution. 5. Role of biology in the conservation of environment. 6. Organisms effecting human health [...]
Parts Of The Environment Lesson 19.1
All factors that make up the environment can be divided into two categories: living and non-living. All living parts of the environment are called biotic factors. Biotic factors in the classroom may include only humans and microbes too small to see. If you were passing through a forest, the list of biotic factors in that [...]
Environmental Biology (10th – Biology – Chapter 19)
In this chapter you learn: 1. Factors that affect an area’s ability to support life. 2. How change in the environment might affect organisms. 3. The structure of an ecosystem. 4. How habitat destruction leads to loss of biodiversity. 5. Roles of producers, consumers and decomposer in the ecosystem. 6. The concept of tropic levels. [...]
Evolution (10th-Biology-Chapter-18)
In this chapter you will learn: Definition of evolution Concept of variation and its causes Role of environment in variation Important characteristics of Lamarck’s theory of evolution (Lamarckism) Salient features of Darwin’s theory of evolution (Darwinism) Comparative anatomy and artificial selection as evidences in support of evolution. Almost two and a half million known kinds [...]
Chromosomes Specific To Their Species
Each kind of organism has a specific number of chromosomes. This number remains constant in all individuals of a species generation after generation. The nucleus of your zygote and each somatic cell of your body that arose from it contain 46 chromosomes. It is the diploid (2n) no. of our species homo sapiens. Similarly frog’s [...]
Genes and their Role in Biological inheritance lesson 17.1
you ever had such a fascinating experience that a stranger had recognized you at a glance, that whose child you are or whose sib you are? How was he able to make such and accurate guess? Was it your charming smile that resembled that of your mother, or your face line was like that of [...]
Genes and Inheritance (10th-Biology-Chapter-17)
In this chapter you will learn: 1. Heredity, genes and their role in biological inheritance. 2. Relationship between genes and chromosomes. 3. Alleles, their origin and impact. 4. Crossing over and its significance. 5. What genes are; chemical composition and structure of DNA. 6. Significance of base sequence in DNA, replication of DNA. 7. How [...]
Importance Of Pollination In Agriculture 16.2-2
Most of the plants used in agriculture are the flowering plants. Pollination leads to fertilization, forming seeds and fruits, which are used as food by us tand other animals. If the process of pollination is damaged by the use of insecticides or pesticides through killing of insects, the fruit formation in orchards and seed formation [...]
