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Reproduction in Animals Introduction Reproduction is the most essential for the continuation of a species. Reproduction ensures the continuation of similar kinds of species, generation after generation. Modes of Reproduction Following are the two modes of reproduction − Sexual reproduction reproduce Asexual reproduction Let us discuss each one separately − Sexual Reproduction In animals, males and females have different reproductive organs. The reproductive parts in animals produce gametes that fuse and form a zygote. The zygote develops into a new similar species. The type of reproduction through the fusion of male and female gametes is known as  sexual reproduction . The male gametes, produced by testes, are known as  sperms . The female gametes, produced by ovary, are known as  ova  (or eggs). In the process of reproduction, the first step is the  fusion  of a sperm and an ovum (egg). Fusion of the egg and the sperm is known as  fertilization  ...

Biology - Sexual Reproduction Introduction The sexual mode of reproduction comprises the process of combining DNA from two different individuals. There are two germ-cells (responsible for producing a new organism); one is large and contains the food-stores whereas the other one is smaller and likely to be motile. The motile germ-cell, normally, is known as the ‘ male gamete ’ and the germ-cell containing the stored food is known as the ‘ female gamete .’ Sexual Reproduction in Flowering Plants As shown in the image given below, flowers have different parts, such as sepals, petals, stamens, and carpels. Among these, stamens and carpels are the reproductive parts and contain the germ-cells. Stamen is the male reproductive part, which produces pollen grains (yellowish substance). Carpel, which is present in the center of a flower, is the female reproductive part. Carpel is made of three parts. The bottom part, which is swollen, is the  ovary ; the middle part, ...

Biology - How do Organisms Reproduce? Introduction A basic occurrence in reproduction is the creation of a DNA copy; to produce copies of the DNA, cells use chemical reactions. The DNA in the cell nucleus is actually the information source for creating proteins. Likewise, if the information is changed here, then different proteins will be created. And, these different proteins will eventually lead to altered the body designs. DNA copies that generated would be similar, but may not be identical to the original. And, because of these variations, the new born cells are slightly different. Further, the consistency of DNA copying during reproduction process is significant for the maintenance of body design and features. Modes of Reproduction Used by Cell Organisms The modes by which various Cell Organisms reproduce depend on their body designs. However, it is broadly categorized as − Asexual Reproduction  & Sexual Reproduction Let’s discuss each of them in Brief − Asexua...

Biology - Hormones in Animal Introduction Human body has different glands (as shown in the image given below) that secret Hormones (liquid substance), which are essential for the different body functions. Adrenaline Hormone is secreted from the adrenal glands. It is secreted directly into the blood and then carried to different parts of the body. On the other hand, plants have hormones that control and regulate their directional growth. Iodine is essential for the thyroid gland that makes thyroxin hormone. Further, Iodine is an essential element for the synthesis of thyroxin. Deficiency of Iodine, that might cause goiter. The term “goiter” refers to the abnormal expansion of the thyroid gland (resulting into swollen neck). Thyroxin Hormone regulates carbohydrate, protein, and fat metabolism in the body and provide the best balance for body growth. Growth hormone, which is secreted by the pituitary gland, regulates growth and development of the body. The deficien...

Biology - Control and Coordination Introduction In multicellular organisms, following the general principles of body organization, some specialized tissues are used to provide the control and coordination activities. Nervous System Nervous system is specialized system that provide control and coordination in animals. All information, coming from our environment is detected by the specialized tips of some nerve cells, which are usually located in sense organs. The information, acquired at the end of the dendritic tip (shown in the image given below) of a nerve cell, sets off a chemical reaction that creates an electrical impulse. This (electrical) impulse, which travels from the dendrite tip to the cell body, and then along the axon to its end of the axon, sets off the release of some chemicals. These chemicals cross the gap, or synapse, and create a similar electrical impulse in a dendrite of the next neuron (see the image given below). Likewise, the nervous tis...

Biology - Excretion Excretion Explained Introduction The biological process that involves in the removal of the harmful metabolic wastes from the human body is known as  excretion . Different species (organisms) use different processes for the excretion. E.g. many unicellular organisms remove their wastes by simple diffusion process from the body surface into the surrounding water. Excretion in Human Beings The body parts that the excretory system (of human beings) includes are − A pair of kidneys A pair of ureters A urinary bladder A urethra Kidneys are located in the abdomen (see the image given below), one on either side of the backbone. Urine that produced in the kidneys passes through the ureters into the urinary bladder where it gets stored until released through the urethra. On the other hand, plants have completely different process for excretion than those of animals. Oxygen (released in the day-time) itself can be considered as a waste product generated during...

  Biology - Reproduction in Animals Introduction Reproduction is the most essential for the continuation of a species. Reproduction ensures the continuation of similar kinds of species, generation after generation. Modes of Reproduction Following are the two modes of reproduction − Sexual reproduction Asexual reproduction Let us discuss each one separately − Sexual Reproduction In animals, males and females have different reproductive organs. The reproductive parts in animals produce gametes that fuse and form a zygote. The zygote develops into a new similar species. The type of reproduction through the fusion of male and female gametes is known as  sexual reproduction . The male gametes, produced by testes, are known as  sperms . The female gametes, produced by ovary, are known as  ova  (or eggs). In the process of reproduction, the first step is the  fusion  of a sperm and an ovum (egg). Fusion of the egg and the sperm is known as  fertilization...

  Biology - Sexual Reproduction Introduction The sexual mode of reproduction comprises the process of combining DNA from two different individuals. There are two germ-cells (responsible for producing a new organism); one is large and contains the food-stores whereas the other one is smaller and likely to be motile. The motile germ-cell, normally, is known as the ‘ male gamete ’ and the germ-cell containing the stored food is known as the ‘ female gamete .’ Sexual Reproduction in Flowering Plants As shown in the image given below, flowers have different parts, such as sepals, petals, stamens, and carpels. Among these, stamens and carpels are the reproductive parts and contain the germ-cells. Stamen is the male reprodujctive part, which produces pollen grains (yellowish substance). Carpel, which is present in the center of a flower, is the female reproductive part. Carpel is made of three parts. The bottom part, which is swollen, is the  ovary ; the middle part, which is elongat...

Some Chemistry  waec keypoints In 2022  We have prepared a more detailed keypoints for interested people, drop your whattsapp number to Get it now for free Amines have a characteristic fishy smell  The industrial preparation of HNO 3  is carried out using Ostwald's process Heavy chemicals are those chemicals used in large quantities in Industries. The most used chemical in industries is H 2 SO 4 . NaOH is used for making soap Fine chemicals are not produced in large quantities. However, they are produced with a high degree of accuracy, e.g AgBr. Fine chemicals include drugs. Thermite process is used for Welding broken ends of metal parts. Bessemer process is used for the production of steel Acheson process is used to produce Graphite Nigerian Crude oil is called sweet because of its low sulphur content. Alkanals can be oxidized but Alkanones cannot, why? It is because Alkanals have an oxidizable hydrogen atom attached to the carbonyl carbon but Alkanones do not. News...

  Jamb/waec most repeated hot topics OVERVIEW Below are tips carefully selected, that jamb/waec sometimes pay attention to in Exams you are encourage to know them 1.     Retina is the part of the eye that is sensitive to light. 2. Population rate or size varies due to factors like natality, mortality, immigration, and emigration 3. The number of offspring produced from a mitotic division is  Two . 4.  Large vacuoles  are absent in animal cells but present in plant cell along with Chloroplast and cellulose cell wall while Chromosomes occur in both. 5. The energy released during cellular respiration is stored in the form of  Adenosine Triphosphate  (ATP) 6. At the end of  mitosis , the number of cells produced is four. 7. During  inspiration , the diaphragm contracts and flattens out simultaneously as the rib muscles contract, causing the ribs to be raised. 8. Each kidney is connected with the bladder by a Ureter. 9. T...

Biology - How Organisms Reproduce Introduction A basic occurrence in reproduction is the creation of a DNA copy; to produce copies of the DNA, cells use chemical reactions. The DNA in the cell nucleus is actually the information source for creating proteins. Likewise, if the information is changed here, then different proteins will be created. And, these different proteins will eventually lead to altered the body designs. DNA copies that generated would be similar, but may not be identical to the original. And, because of these variations, the new born cells are slightly different. Further, the consistency of DNA copying during reproduction process is significant for the maintenance of body design and features. Modes of Reproduction Used by Cell Organisms The modes by which various Cell Organisms reproduce depend on their body designs. However, it is broadly categorized as − Asexual Reproduction  & Sexual Reproduction Let’s discuss each of them in Brief − Asexual Reproduction A...

Biology - Hormones in Animal Introduction Human body has different glands (as shown in the image given below) that secret Hormones (liquid substance), which are essential for the different body functions. Adrenaline Hormone is secreted from the adrenal glands. It is secreted directly into the blood and then carried to different parts of the body. On the other hand, plants have hormones that control and regulate their directional growth. Iodine is essential for the thyroid gland that makes thyroxin hormone. Further, Iodine is an essential element for the synthesis of thyroxin. Deficiency of Iodine, that might cause goiter. The term “goiter” refers to the abnormal expansion of the thyroid gland (resulting into swollen neck). Thyroxin Hormone regulates carbohydrate, protein, and fat metabolism in the body and provide the best balance for body growth. Growth hormone, which is secreted by the pituitary gland, regulates growth and development of the body. The deficiency of growth hormone in ...

Biology - Control and Coordination Introduction In multicellular organisms, following the general principles of body organization, some specialized tissues are used to provide the control and coordination activities. Nervous System Nervous system is specialized system that provide control and coordination in animals. All information, coming from our environment is detected by the specialized tips of some nerve cells, which are usually located in sense organs. The information, acquired at the end of the dendritic tip (shown in the image given below) of a nerve cell, sets off a chemical reaction that creates an electrical impulse. This (electrical) impulse, which travels from the dendrite tip to the cell body, and then along the axon to its end of the axon, sets off the release of some chemicals. These chemicals cross the gap, or synapse, and create a similar electrical impulse in a dendrite of the next neuron (see the image given below). Likewise, the nervous tissue is made up of an org...