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Ask QuestionPosted by Takshi Pravinaa A P 3 years, 11 months ago
- 3 answers
Gaurav Seth 3 years, 11 months ago
- The function and significance of vacuoles vary greatly according to the type of cell in which they are present.
- In general, the functions of the vacuole include- Isolating materials that might be harmful or a threat to the cell. Containing waste products.
- Containing water in plant cells. Maintaining internal hydrostatic pressure or turgor within the cell. Maintaining an acidic internal pH.
- Allows plants to support structures such as leaves and flowers due to the pressure of the central vacuole etc.
Posted by Niharika Singh 3 years, 11 months ago
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Meghna Thapar 3 years, 10 months ago
Adolescence is a critical link between childhood and adulthood, characterized by significant physical, psychological, and social transitions. These transitions carry new risks but also present opportunities to positively influence the immediate and future health of young people. Children are like wet clay, you can mold them in any shape. They are quick learners and absorb everything around them with their audio-visual senses.
Posted by Amisha Verma 3 years, 11 months ago
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Bani Singh Bani Singh 3 years, 11 months ago
Divyansh Jain 3 years, 11 months ago
Nayan Joshi 3 years, 11 months ago
Gaurav Seth 3 years, 11 months ago
- Reproduction is the process of giving rise to an offspring.
- Reproduction is essential for the continuation of a species.
- There are two modes of reproduction:
- Sexual reproduction and
- Asexual reproduction
Posted by Smitha Smitha 3 years, 11 months ago
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Prachi Saxena 3 years, 11 months ago
Ram Budania 3 years, 11 months ago
Avinash Singh 3 years, 11 months ago
Aishwarya Wagh 3 years, 11 months ago
Yogita Ingle 3 years, 11 months ago
Hormones are chemicals synthesized and produced by the specialized glands to control and regulate the activity of certain cells and organs. These specialized glands are known as endocrine glands.
Posted by Sakshi Chouhan 3 years, 11 months ago
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Gaurav Seth 3 years, 11 months ago
A cell is the structural and fundamental unit of life. The study of cells from its basic structure to the functions of every cell organelle is called Cell Biology. Robert Hooke was the first Biologist who discovered cells.
Cell Structure
The cell structure comprises individual components with specific functions essential to carry out life’s processes. These components include- cell wall, cell membrane, cytoplasm, nucleus, and cell organelles. Read on to explore more insights on cell structure and function.
Cell Membrane
- The cell membrane supports and protects the cell. It controls the movement of substances in and out of the cells. It separates the cell from the external environment. The cell membrane is present in all the cells.
- The cell membrane is the outer covering of a cell within which all other organelles, such as the cytoplasm and nucleus, are enclosed. It is also referred to as the plasma membrane.
- By structure, it is a porous membrane (with pores) which permit the movement of selective substances in and out of the cell. Besides this, the cell membrane also protects the cellular component from damage and leakage.
- It forms the wall-like structure between two cells as well as between the cell and its surroundings.
- Plants are immobile, so their cell structures are well-adapted to protect them from external factors. The cell wall helps to reinforce this function.
Cell Wall
- The cell wall is the most prominent part of the plant’s cell structure. It is made up of cellulose, hemicellulose and pectin.
- The cell wall is present exclusively in plant cells. It protects the plasma membrane and other cellular components. The cell wall is also the outermost layer of plant cells.
- It is a rigid and stiff structure surrounding the cell membrane.
- It provides shape and support to the cells and protects them from mechanical shocks and injuries.
Cytoplasm
- The cytoplasm is a thick, clear, jelly-like substance present inside the cell membrane.
- Most of the chemical reactions within a cell take place in this cytoplasm.
- The cell organelles such as endoplasmic reticulum, vacuoles, mitochondria, ribosomes, are suspended in this cytoplasm.
Nucleus
- The nucleus contains the hereditary material of the cell, the DNA.
- It sends signals to the cells to grow, mature, divide and die.
- The nucleus is surrounded by the nuclear envelope that separates the DNA from the rest of the cell.
- The nucleus protects the DNA and is an integral component of a plant’s cell structure.
Posted by Diksha Laniya🐥 3 years, 11 months ago
- 5 answers
Gaurav Seth 3 years, 11 months ago
Decrease
Oils, grease, graphite, etc., are examples of lubricants. These form a thin layer between the two surfaces in contact thus avoiding them from scrubbing directly against each other. This makes the movement smooth and reduces friction.
Sakshi Chouhan 3 years, 11 months ago
Posted by Diksha Laniya🐥 3 years, 11 months ago
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Sakshi Chouhan 3 years, 11 months ago
Gaurav Seth 3 years, 11 months ago
Gravitational force
Gravitational force is a force exerted by the earth on all objects on it. When a ball is thrown up, it falls to the ground because of gravitational force. The water from a tap always flows downwards because of gravitational force.
Posted by Diksha Laniya🐥 3 years, 11 months ago
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Gaurav Seth 3 years, 11 months ago
drag
The frictional force exerted by a fluid is called drag.
Drag is a kind of frictional force exerted by fluid which opposes the motion of an object through that fluid.
Posted by Diksha Laniya🐥 3 years, 11 months ago
- 4 answers
Gaurav Seth 3 years, 11 months ago
Non-contact forces: Forces that arise without the contact of 2 or more objects involved. Examples: Magnetic Force, Electrostatic Force, Gravitational force.
Magnetic Force is a force that attracts certain metal objects (like iron and iron filings) towards a magnet.
Electrostatic force is the force exerted by a charged body on another charged or uncharged body. Eg: Take a comb and brush it on a hair 3-4 times and then take it near some small bits of paper. Donot touch the comb with the paper. The bits of paper would get attracted to the comb. This is because the comb is charged because of the rubbing on your hair and it attracts uncharged objects like paper.
Gravitational force is a force exerted by the earth on all objects on it. When a ball is thrown up, it falls to the ground because of gravitational force. The water from a tap always flows downwards because of gravitational force.
Posted by Diksha Laniya🐥 3 years, 11 months ago
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Posted by Diksha Laniya🐥 3 years, 11 months ago
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Posted by Diksha Laniya🐥 3 years, 11 months ago
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Drishti Ranjan 3 years, 11 months ago
Posted by Diksha Laniya🐥 3 years, 11 months ago
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Yogita Ingle 3 years, 11 months ago
True
Estrogen is widely secreted and released by a pair of ovaries in the female gonad and only a small amount of estrogen is released by the adrenal glands and fat cells, which is responsible for sexual and reproductive development during puberty.
Posted by Diksha Laniya🐥 3 years, 11 months ago
- 3 answers
Yogita Ingle 3 years, 11 months ago
True
Humans are diploid (2n) and have 46 chromosomes in their normal body cells. These 46 chromosomes are organized into 23 pairs: 22 pairs of autosomes and 1 pair of *** chromosomes.
Posted by Diksha Laniya🐥 3 years, 11 months ago
- 2 answers
Posted by Diksha Laniya🐥 3 years, 11 months ago
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Gaurav Seth 3 years, 11 months ago
Internal fertilization occurs in many animals including humans, cows, dogs and hens.
Fertilization which takes place inside the female body is called internal fertilization. Internal fertilization occurs in many animals including humans, cows, dogs and hens. In many animals fertilization takes place outside the body of the female. In these animals, fertilization takes place in water
Posted by Diksha Laniya🐥 3 years, 11 months ago
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Gaurav Seth 3 years, 11 months ago
The normal duration it takes for the development of the fetus from the time of fertilization in the womb of its mother is called the gestation period. In humans, the gestation period is for about 9 months or approximately 280 days. It is calculated from the incipience of their last menstrual period.
Posted by Diksha Laniya🐥 3 years, 11 months ago
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Gaurav Seth 3 years, 11 months ago
The type of reproduction in which only a single parent is involved is called asexual reproduction
In asexual reproduction, only one parent is involved. Get permanent slides of hydra,Observe them using hand lens or a microscope. Look out for any bulges from the parent body. Count the number of bulges that you see in different slides. Also, note the size of the bulges.
Posted by Diksha Laniya🐥 3 years, 11 months ago
- 4 answers
Gaurav Seth 3 years, 11 months ago
Fertilization
Fertilization is the process of fusion of a sperm with an ovum. The union of sperm and egg results in the formation of zygote or fertilized egg. In humans, it usually occurs in the fallopian tube. Usually, one sperm fertilizes the ovum. However, there are chances of more than one sperm fertilizing with an ovum. The phenomenon is called as polyspermy.
Posted by Niki Gupta 3 years, 11 months ago
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Yogita Ingle 3 years, 11 months ago
Development of an embryo inside the female body : The zygote formed after fertilization in the fallopian tubes is implanted in the uterus. The uterus is also known as the womb. Here, the zygote divides to form an embryo, which develops into a foetus.
The outer-thin layer is known as the perimetrium.
The middle layer is thick and is made up of smooth muscles. It is known as the myometrium. These muscles contract strongly during the delivery of a baby.
The inner layer lines the uterine cavity, which has many glands and is known as the endometrium. It thickens every month and is supplied with blood to nourish the embryo. It undergoes cyclic changes during the menstrual cycle.
Shruti ? 3 years, 11 months ago
Posted by Ravi Kumar Kumar 3 years, 11 months ago
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Posted by Shruti ? 3 years, 11 months ago
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Gaurav Seth 3 years, 11 months ago
Answer:
In human beings, body parts of an adult are present from the time of birth itself. Whereas, in metamorphosis, the parts of the adult are different from those at the time of birth.
Posted by Shruti ? 3 years, 11 months ago
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Posted by Shruti ? 3 years, 11 months ago
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Gaurav Seth 3 years, 11 months ago
| The term embryo is from Latin work “embryum” which means “that which grows” |
| Embryo is multicellular |
| The process of formation of embryo is known as embryogenesis |
| In medical terms, embryo is known as diploid eukaryote |
|
Zygote |
Foetus |
| It is formed by the fusion of the nuclei of the sperm and egg. | It is the stage of the embryo which nearly resembles a human being. |
| It is a unicellular structure. | It is a multicellular structure. |
| Produced after the processes of fertilization. | Produced after the processes of cell division and cell labour division. |
| In Zygote well-described body are absent. | In Foetus well-described body parts are present. |
Posted by Vipin Verma 3 years, 11 months ago
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Meghna Thapar 3 years, 11 months ago
The pituitary gland sits below the brain in a midline pocket or fossa of the sphenoid bone known as the sella turcica, imaginatively named by anatomists because of its likeness to a Turkish horse saddle. Embryologically, anatomically and functionally the human gland is divided into two lobes. The anterior lobe constitutes two thirds of the volume of the gland and the posterior lobe one third. As with all other endocrine glands, symptoms arise as the result of either hypo- or hypersecretion of hormones.
Posted by Yash Saharan Saharan 3 years, 11 months ago
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Dipal Khatri 3 years, 11 months ago
Everything Here 3 years, 11 months ago
Yogita Ingle 3 years, 11 months ago
Plastic or rubber is an insulator which does not allow electric current to pass through it. The handles of the tools like screwdrivers and pliers used by electricians for repair have covering of plastic or rubber so that electric current may not pass through these tools to the body of the electrician to harm him.
Avani Rana 3 years, 11 months ago
Posted by Manish Sharma 3 years, 11 months ago
- 2 answers
Avani Rana 3 years, 11 months ago
Gaurav Seth 3 years, 11 months ago
The burning of a substance in the presence of oxygen is defined as combustion.
Conditions necessary for combustion are:
(i) Presence of a combustible substance.
(ii) Attainment of ignition temperature.
(iii) Proper supply of air to provide oxygen.
Structure of flame
A flame consist of three zones.These are Innermost zone,middle zone,outer zone.The three zones of a flame have different colours and different temperature.
Posted by Preyasi Jain 3 years, 11 months ago
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Gaurav Seth 3 years, 11 months ago
a N S W E R :
a. contraction v) expanded sound waves
b. rarefaction iii) compressed sound waves
c. amplitude iv) loudness of sound waves
d. cochlea i) coiled organ of hearing
e. semi-circular canals ii) organs of balance
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Nayan Joshi 3 years, 11 months ago
1Thank You