1. The passing of traits from parents to the offsprings (children) is the basis of heredity. Traits are notable features or qualities in a person, such that each individual has a different combination of traits that makes us unique from others. They are inherited from our parents and passed from generation to generation. That is to our children, then our children to their children and so on.
2. Our genes encode the instructions that define our traits. Traits are majorly defined by the instructions encoded in the genes. However, environment may influences the traits and may play an important role in shaping the traits we posses. Often times these traits may be changed by the environmental factors.
3. Each of us has thousands of genes, which are made of DNA molecules and reside in our chromosomes. Genes are functional or fundamental units of heredity. They are made up of DNA molecules, and act as instructions to make proteins, through a process of transcription and translation. Transcription involves formation of a messenger RNA which then undergoes translation in the cytoplasm to make proteins.The protein formed determine the traits of an individual.
4. In addition to our genes, the Environment we live in also helps define our traits. The expression of genes in organisms may be influenced by environmental factors, these includes the external factors where the organism lives or develops, and also the internal factors such as its hormones and metabolism.
5. Human have two complete sets of 23 chromosomes. A human being has a total of 46 chromosomes (23×2 = 46). This is referred to as a diploid number (2n). Each set is considered to be a one homologous chromosome set. This is the case of of the somatic cells or the body cells which represents a diploid number of chromosomes.
6. When parents conceive a child, each parent contributes one set of chromosomes.This enhances the passing of traits or genes to the child. The egg cell or the ovum from the mother and the sperm cell from the father contain the haploid number (n) or one set of chromosome. During conception the two combines/fuse to form a zygote which is now diploid (2n).
7. Every child receives half of its chromosomes from the mother and another half from the father. During meiosis in the gametes for both mother and father a haploid cell is formed with one set of chromosomes (haploid, n). Therefore, each child contains half number of chromosomes from the mother and the other half from the father making up the diploid number (2n).
8. This transfer takes place at conception, when the father's sperm joins the mother's egg. During conception, fertilization takes place and the sperm cell fuses with the mother cell (ovum) forming a single cell called Zygote. The zygote has the two sets of chromosomes (23 +23 = 46). The cells then divide by mitosis leading to the development of a child.
9. While most cells in our bodies have two sets of chromosomes, or a total of 46 chromosomes, egg and sperm each have 23 chromosomes. The body cells (somatic cells) contain two sets of chromosomes (diploid number, 2n) from mitosis, while the gametes have a single set of chromosomes (haploid, n), from meiosis.
Hello! The interaction between the two system is an inter-dependent relationship. An example of this is that the heart pumps arterial blood to the circulation. The deoxygenated or venous blood returns to the lung where blood is oxygenated. Then the blood flows into the heart chambers and the cycle continues on.
Answer:
The excretory system helps the respiratory system by removing carbon dioxide that is produced during respiration (third option).
Explanation:
The lungs are in charge of the breathing process, being the main organ of the respiratory system. Each lung is considered an excretory organ —belonging to the excretory system— since it is capable of eliminating the carbon dioxide (CO₂) produced by the metabolism during expiration.
As a result of the gaseous exchange, the oxygen entering the lungs through the inhaled air passes into the blood, while the CO₂ is removed from the blood. This CO₂ is removed during expiration, which makes the lungs part of the excretory system.
The other options are not correct because:
- <em>The excretory system does </em><u><em>not introduce more oxygen into the lungs</em></u><em>.
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- <em>The </em><u><em>circulation of blood in and out of the lungs</em></u><em> is a function of the circulatory system.
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- <u><em>Urine is not produced by breathing</em></u><em>.</em>