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The term ‘mitosis’ was coined by Walther Flemming in 1882 and derived from the Greek word ‘mitos’ meaning ‘warp thread’. Example: Healing of wounds, where damaged cells are replaced and repaired by forming new cells. How Long does it Take to Complete For most cells, mitosis takes around one and a half to two hours on an average to complete. G1-phase: The first growth phase of the cell cycle, it is the resting stage during which some cell organelles increase in size, and the cells rapidly synthesize the different types of RNA and proteins....

Otto cycle is named after German engineer Nikolas Otto, the first to build a working four-stroke engine in 1876. Process Efficiency 0 → 1 Intake stroke: Air-gas mixture is drawn into the engine at constant pressure. 1 → 2 Compression stroke: Adiabatic (isentropic) compression of the gas, resulting in increased temperature and pressure. 2 → 3 Combustion: Heat transfer from an external source to the mixture at constant volume resulting in the ignition—temperature and pressure increase....

Huygens’ Principle According to Huygens’ principle, every unobstructed point on a wavefront will act as a source of secondary spherical waves. The new wavefront is the surface tangent to all the secondary spherical waves. Therefore, each part of the slit can be thought of as an emitter of waves. We assume that the screen is at a considerable distance from the slit, i.e., D » a. Hence, θ = θ’ And, sin θ ≈ tan θ ≈ θ = y/D The path difference between the two rays AP and BP is given by, Δ = BP – AP = BC In the right-angled triangle BCA, sin θ’ = sin θ = BC/BA BC = BA sin θ = a sin θ Therefore, Δ = a sin θ Diffraction Minima The condition for minima or dark fringe is, Path difference = integral multiple of wavelength or, Δ = nλ (n=±1, ±2, ±3, … , etc....

Thermal radiation does not require any medium to propagate and can travel through a vacuum. This property makes thermal radiation unique compared to conduction and convection. However, it can be dangerous because the heating effect can cause burns and damage the skin. Examples Planck-Einstein Relation Thermal Radiation Equations The Sun emits thermal radiation, which we perceive as warmthAn electric stove emits thermal radiation, which cooks foodA campfire emits thermal radiation, which we receive as heatA candle radiates heat....

Nevertheless, how are proteins made? Proteins synthesis occurs using the information in the DNA of a cell. The first step, called transcription, involves rewriting the information in DNA to mRNA. In contrast, the second step is called translation. Thus the main purpose of translation is to convert the information in mRNA into a particular sequence of amino acids (a polypeptide chain), forming a protein. Where does Translation Occur in the Cell Components of Translation What is a Genetic Code in Translation What Happens During Translation What is the Fate of the Protein after Translation 2....

The first vascular plants evolved during the mid-Silurian period, about 410 million years ago. They probably evolved from moss-like bryophyte ancestors. Characteristics Types Xylem transports water and associated minerals from roots to all plant parts. It consists of dead cells lacking end walls between adjacent cells. The sidewalls of the xylem are thickened with lignin deposition making them stiff and waterproof.Phloem transports food (sugar dissolved in water) from leaves to other plant parts for growth and storage....

It is a light-independent process, similar to photosynthesis taking place in the dark. All the autotrophs, algae, bacteria, and plants fix CO2 primarily by photosynthesis. However, some organisms also use chemosynthesis in the absence of sunlight. Where Does It Occur Why is Carbon Fixation Important What Happens During the Process Why There Are Different Types of Carbon Fixation in Plants The balance between carbon fixation during photosynthesis and the release of CO2 during respiration affects overall plant growth....

Sun emits vast neutrinos that pass through layers of the earth with little or no interaction. The solar neutrino flux produces about 5 x 106 neutrinos/cm2s. Neutrinos belong to the family of leptons that are not subject to the strong force. They are denoted by the symbol ‘n’. Neutrinos play fundamental aspects of our lives produced in nuclear fusion processes that power the sun and stars. They are also released from radioactive decay....

Eukaryotic cells, plant or animal, often contain a single nucleolus, though several are also possible. The exact number is fixed among the members of the same species. Each human diploid cell contains only one nucleolus formed at specific chromosome sites known as nucleolus organizer regions (NORs). The DNA found at chromosomal NORs encodes the genes for ribosomal RNA (rRNA). At the start of mitosis, the single nucleolus disappears and is again reassembled from 10 smaller nucleolus-like structures that develop from the NORs during the telophase and early G1 phase of the cell cycle....

The marine biome is the largest worldwide, covering three-quarters of the Earth’s surface. About 15% of all the species living on Earth, containing almost 300,000 species, are marine dwellers. The marine ecosystem consists of a series of interconnected producers and consumers. Example Level 1: Primary Producers (Photoautotrophs) Level 2: Primary Consumers (Herbivores) Level 3: Secondary Consumers (Carnivores) Level 4: Tertiary Consumers (Top Predators) Alternative Ocean Food Chains Like terrestrial food chains, the primary ocean food chain also has different levels....

The parallel axis theorem is a convenient way to calculate the moment of inertia about any parallel axis since the moments of inertia few familiar objects can be found in tables. Formula Derivation When to Use Parallel Axis Theorem Example Problems IO = IC + Md2 IC is the moment of inertia about an axis passing through the center of mass. IO is the moment of inertia about an arbitrary axis parallel to the axis passing through the center of mass....

What Causes Paramagnetism Paramagnetic Materials Magnetic Susceptibility of Paramagnetic Materials Applications Elements Molecules Magnetic susceptibility depends upon the temperature according to Curie’s law. The law states that the magnetic susceptibility of a material is inversely proportional to its absolute temperature (T). In equation form, this relationship can be expressed as: Here, C is called the Curie constant, a characteristic property of the material that depends on the strength of the atom and the density of magnetic moments....

When and Where Does Substrate-level Phosphorylation Occur Substrate-level Phosphorylation in Glycolysis Substrate-level Phosphorylation in Krebs Cycle (Citric Acid Cycle) Importance of Substrate-level Phosphorylation Step 1: First, a phosphoryl group gets transferred from 1, 3-bisphosphoglycerate to ADP, forming 3-phosphoglycerate (3PG) and ATP. This step is catalyzed by phosphoglycerate kinase (PGK), giving off 2 ATPs. 2 (1,3-bisphosphoglycerate) + 2 ADP → 2 (3-phosphoglycerate) + 2 ATP Step 2: Second, a phosphoryl group is transferred from two phosphoenolpyruvate (PEP) molecules to ADP, forming two pyruvate molecules and ATPs....

It forms spherical or oval colonies, as small as the size of a pinhead with a hollow mucilaginous mass, with each colony containing almost 50,000 cells. Dutch microscopist Antonie van Leeuwenhoek first observed Volvox in 1700. Where do they Live Volvox are found throughout the world, inhabiting various temporary and permanent freshwater-bodies such as tanks, ponds, lakes, ditches, and puddles. They exist by forming colonies known as coenobium. They multiply fast in nutrient-rich environments, especially during the rainy season, often causing their habitat water-bodies to turn green....

Where are Contractile Vacuoles Found Function: What does the Contractile Vacuole Do As we know, the tonicity or the concentration of solutions should remain the same in the intracellular and extracellular space for the proper functioning of the cell. So, whenever there is an imbalance in solution concentration, the cells undergo a specialized process called osmoregulation. Osmoregulation is the process of regulating a constant osmotic pressure of the cellular fluid by controlling the water flow and solute concentrations relative to the surrounding....

Electric Flux Equation Applications of Electric Flux Problems and Solutions Where, Mathematically, the electric flux is given by the dot product of the electric field vector and area vector. Where If the angle between the electric field vector and the area vector is θ, then the dot product can be expanded to give the magnitude of electric flux. Symbol: φ or phi SI Unit: Volt-meter (V-m) or Newton per meter-squared per Coulomb (Nm2C-1) CSG Unit: stat Coulomb (statC) or Franklin (Fr) (1 C = 3 x 109 statC) Dimension: [M L3 T−3 A−1] When θ = 0˚, cos 0˚ = 1, therefore, φ = EA Therefore, the maximum number of electric field lines will pass through a surface placed perpendicular to the electric field....

What does Gauss’s Law State According to Gauss’s law, the electric flux through any closed surface is proportional to the total electric charge enclosed by this surface. Gauss’s law has been named after German mathematician and physicist Karl Friedrich Gauss, who postulated it in 1867. Conditions of Gauss’s Law Gauss’s Law Equation Derivation of Gauss’s Law Importance and Applications of Gauss’s Law Where, φ: Electric Flux Qenc: Charge enclosed ε0: Permittivity of free space (= 8....

It is essential because it helps plants grow, repair, regenerate after injury, and produce and store food as carbohydrates. Finally, ground tissue provides structural support in plants and the floating capacity in aquatic plants. Types of Cells in Ground Tissue with Functions 1. Parenchyma They are living, undifferentiated cells that can divide and differentiate into all cell types (totipotent). Parenchyma is the most abundant ground tissue in plants. They have primary cell walls, which are thin and flexible and mostly lack a secondary cell wall....

All stars go through roughly the same life cycle. However, their life spans vary greatly, as well as how they eventually die. What Determines the Life Cycle of a Star Stars Based on Their Mass Different Stages of a Star’s Life Cycle 2. Medium Mass Stars Medium mass stars have a mass anywhere from 0.5 to around 3 solar masses. They burn orange and yellow and have an average lifespan of around 5-15 billion years....

Properties of Magnetic Field Lines Examples of Magnetic Field Lines Closed and continuous curveDensity determines the magnetic field strength – crowding of field lines indicates a strong magnetic fieldDensity decreases with increasing distance from the objectThe magnetic field and magnetic force are tangential to the linesThe lines never cross each other. If they do, the tangent at the point of intersection will show different directions, which is not possible Properties of Magnetic Field Lines of a Bar Magnet Apart from the properties discussed in the previous section, the magnetic field lines of a bar magnet have the following additional properties....