Chapter 1
Cell Biology
1. Who first noticed cells?
Answer : Cells were first observed by Robert Hooke.
2. What are the two main parts of a cell?
Answer : The two main parts of a cell are the cytoplasm and the nucleus.
3. What are the two main types of human cells?
Answer : The two main types of human cells are reproductive cells and somatic cells.
4. The Define cells.
Answer : According to Loy and Seikevitz, "A cell is the smallest unit of the fundamental structure and function of all living organisms which is capable of independent existence and self reproduction of a suitable environment. ("The cell is the smallest unit of basic structure and function of all organisms capable of independent existence and self-reproduction of a suitable environment.")
5. What is meant by cell division?
Answer : The process by which cells in an organism divide to form their microscopic progeny cells is called cell division.
6. Who first proposed the idea of cell division?
Answer : The concept of cell division was first proposed by Hofmeister in
7. Mitosis What are the stages of cell division?
Answer : Mitosis There are four stages of cell division.
8. Who first described the term chromosome?
The term chromosome was first described by Steusberger in 1975
9. What is the number of chromosomes in the human body?
Answer : There are 46 chromosomes in the human body.
10. Name two types of proteins on chromosomes?
Answer : There are two types of proteins in chromosomes called histones and non-histone proteins. 11. 11. What does the word gene come from?
Answer : The word gene comes from the Greek word 'genome' 12. Draw a human cell and show its different parts.
Answer: -
13. Mitosis Describe the cell division.
Answer : Mitosis is the cell division involved in the intelligence and development of the body tissues of multicellular organisms. This division is universal and can be found in the cells of any animal, from the smallest to the largest. In this process, the nuclear envelope is first removed. The chromosomes then become clear and divide equally into two parts to form two progeny nuclei. A cell wall is formed between the two newly formed nuclei. This wall also divides the cytoplasm equally. This process is called cytokinesis.
The continuous changes in the cell nucleus during cell division through mitosis are divided into four stages. Those parts are 一
(i) Prophase
(ii) Metaphase
(iii) Anaphase
(iv) Telophase
The above sections are discussed in more detail below
(i) Prophase: - The first stage of nucleus division is the prophase. During the initiation of cell division, the cell remains stationary. As this stage begins, the nucleus becomes slightly larger in size and the nucleus mesh disappears. Chromotins in the nuclear membrane are converted into thread-shaped chromosomes. At the beginning of this division, the chromosomes take the shape of a curved thread of cacao and each chromosome divides lengthwise into two parts by the method of nucleopathy. The two parts are homogeneous.
(ii) Metaphase: - With the onset of metaphase, the nucleus and the nuclear envelope of the cell nucleus become completely invisible. Cytoplasmic fibers move from the two poles of the cell to the middle part of the cell. This causes the middle to become thicker and gradually smaller on both sides. This is called the central mohura. This cavity extends from end to end to the middle of the cell.
(iii) Anaphase: - Anaphase begins as the chromatid attachment contracts and moves towards two opposite poles. In this condition, the chromosomes separate from each other. Fibers attached to the centromere begin to pull the chromatid to the two poles. Thus, one of the homologous chromatids moves to one pole and the other to the other.
(iv) Telophase: - At the end of the telophase movement, the chromosomes are clustered at the two poles of the cell. These chromatids are called chromosomes. Gradually, the chromosomes become finer and longer, leaving the twisted state and assuming their previous shape. In other words, it gradually becomes obscured. The cocoon has already disappeared. Instead, the chromosomes are surrounded by the nuclear envelope. The nucleolus also preforms.
14. Distinguish between mitosis and meiosis cell division.
Answer: - The differences between mitosis and meiosis cell division are mentioned below一
(i) The body cells of an organism divide by the process of mitosis. On the other hand, the reproductive cells of an organism divide through the process of meiosis.
(ii) Mitosis Cell division results in the growth of somatic cells in an organism. Meiosis, on the other hand, causes the reproductive cells of an organism to grow as a result of cell division.
(iii) In mitosis, a cell divides once to form two daughter cells. In meiosis, on the other hand, a cell divides twice to form four daughter cells.
(iv) Mitotic homologous chromosomes do not pair. On the other hand, meiosis homologous chromosomes pair.
(v) mitosis Kayzama is not formed during cell division. Meiosis, on the other hand, occurs during cell division.
(vi) Mitosis The intermediate stage of cell division is prolonged. On the other hand, the intermediate stages of the meiosis cell division process are transient.
(vii) Mitosis The initial stage of cell division is very simple and does not divide into sub-stage. On the other hand, the early stages of meiosis are very complex and long lasting. It is divided into several sublayers.
(viii) Genes are not exchanged between chromosomes during mitosis. Meiosis, on the other hand, involves the exchange of genes between chromosomes.
(ix) Mitosis The process of cell division was first discovered by Walther Flemming. Meiosis, on the other hand, was first discovered by Oscar Hertwig.
15. Diagram of the different parts of a chromosome.
Answer: -
16. Describe the different parts of the chromosome.
Answer : The different parts of the chromosome are discussed in detail below
(i) Pellicle: - Each chromosome is covered with a thin membrane. This covering is called the pellicle.
(ii) Chromyma: - The base material covered by the pellicle shows some fine thread-like structures that are twisted at length. These are usually twisted coils of double-stranded DNA. These are called sequences. There are two types of chromatic horoscopes:
paranemic coil and pectonemic coil.
(iii) Centromere: - A clear unstained narrow section is found at a point on each chromosome. This part is called the centromere or primary narrow. The position of the centromere varies from chromosome to chromosome.
(iv) Secondary contraction: - Secondary contraction is a contraction at any place of the chromosome other than the centromere .
(v) Satellite: - Satellite refers to the end of a chromosome that is separated from the main chromosome by a secondary constriction.
(vi) Telomere: - The last end of the chromosome is called the telomere. One of its properties is that it is never interrupted.
17. What are the types of nucleic acids and what are they?
Answer : There are two types of nucleic acids. They are deoxyribonucleic acids and ribonucleic acids.
18. Mention the size of the cell.
Answer : Cells are small in size. Therefore, most cells cannot be seen with the naked eye. Can only be seen under a microscope. Cells come in a variety of sizes. For example, it ranges from 80mu to 1 m. Some cells are much larger and can be seen with the naked eye. Nerve cells are said to be the longest. In humans, cells range in size from 3-4 M (leukocytes) to 90 cm. (nerve cells) are seen.
Cell size is related to the function of cells. Some cells such as blood leukocytes and amoebae may change cell size. But some of them stay the same size. Cells are usually spherical, oval, round or elongated, cuboid, tubular, tubular, polygonal, unevenly spherical, etc.
19. Who first used the terms mitosis and meiosis?
W. Flemming in 1882 described mitosis and J. Flemming . B.Sc.was first usedby JB Farmer and Mooro in
20. What does the word chromosome mean?
Answer : The word chromosome means 'chroma' means color and 'choma' means body.
21. Who first used the term catalyst?
The term catalyst was first used by Friedrich Wittelm Quinn (in 1878) .
22. Describe the functions of catalysts.
Answer : Catalysts are found in all situations. All living organisms need enzymes to function properly. Chemical properties Catalysts are naturally produced proteins whose main function is to accelerate chemical processes. This is a proteinaceous catalyst. The main functions of enzymes are to act as catalysts in all chemical processes such as digestion, reproduction, respiration, development, blood clotting, transmission of diseases and many other biological functions. Catalysts are synthetic substances that help in all the functions of living organisms in biological functions.
(i) Signal transducers : - In signal transducers, enzymes are transduced by cells as chemical or physical signals to form a molecular sequence. The most essential catalyst of signal transduction catalysts is protein phosphorylation.
(ii) Land molecule degradation: - Large molecules broken down and reduced by enzymes in the human body are easily absorbed. The human body cannot absorb many chemicals that are large molecules such as sugars, proteins and fats. Catalysts break these materials into small pieces before they are absorbed and this process is called waste.
(iii) Energy production: - Energy production of living organisms is done by these enzymes. ATP or adensinine triphosphate is the storehouse of chemical energy in these living organisms. ATP is produced by physical activity. derives its energy from. A.T.P. Catalysts act as converters of energy production to store energy in molecules so that it takes the proper chemical form. Such catalysts are called AT. P.S. It is called the destroyer.
(iv) Ion Pumps: - For an active transport function, some enzymes act as ion pumps to carry ions to the plasma membrane according to the concentration in the cell membrane. This primary ion transport position converts it into energy and does this function from a variety of sources those sources are, A.T. P.S. Sunlight and corrosion, etc. from which strong energy can be stored in electrochemical trends.
(v) Defense and purification: - In any organism, the body always produces certain nutrients from the external environment which cannot be the building blocks of the cells or the source of energy production. They must be converted into products that act as functional pathological or biotoxic agents in the body. In this type of process, catalysts alone or several catalysts together or catalysts will carry out biochemical processes such as oxidation, sub-degradation and hydrolysis.
(vi) Cell regulation: - Enzymes can reach the inside of the cell to regulate cell functions. They move from the inside of the cell to another part of the cell and pull chromosomes to other parts of the cell to help the cell move during mitosis or by cleaning the cell membrane. Catalysts are found in all situations.
Additional FAQ:
1. What is the cell membrane?
Answer: Every cell is covered by an inanimate membrane and this is called the cell membrane.
2. What is "Yak"?
Answer: Eggs and eggs in the human body contain a lot of nutrients. This is called "Yak"
3. What is the name of the largest cell in the human body?
Answer: The largest cell in the human body is called the egg.
4. The What is fertilization?
Answer: The union of a sperm and an egg is called fertilization.
5. What is a zygote? How does it take the form of a human-shaped child?
Answer: The fertilized egg is called a zygote.
After fertilization, the zygote begins to divide. Such divisions result in the formation of an embryo that grows in size and becomes a human-shaped baby.
6. What is the cell membrane made of?
Answer: The cell membrane is made up of cellulose fibres.
7. What is the size of the finest and largest cells?
Answer: The size of the finest cell is 80 mu and the size of the largest cell is 1 m.
8. Which cells are the longest?
Answer: Nerve cells.
9. Name a unicellular organism.
Answer: Amoebae.
10. What are the types of reproductive cells?
Answer: There are two types.
11. D.Sc. N.S. A. Write the complete form of (DNA).
Answer: Deoxyribonucleic Acid .
12. What reproductive cells do men have?
Answer: XY
13. What reproductive cells does a woman have?
Answer: XX
14. DNA is a skeletal muscle. (DNA) What is it?
Answer: DNA. (DNA) is a type of nucleic acid. It absolutely means deoxyribo nucleic acid. It carries hereditary traits from parents to children.
23. How many types of nucleic acids are there and what are they?
Answer: There are two types of nucleic acids. They are 一 deoxyribonucleic acid and ribonucleic acid.
