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Science

Alcohol is being consumed by a person , it goes into Gastrointestinal tract and get absorbed by the blood vessels present in small intestine. Through blood, it gets into all cells of body including...

Latest answer posted December 4, 2021, 4:22 am (UTC)

1 educator answer

Biology

There are several things which could cause a woman's progesterone to be higher than expected at this point in her cycle, including pregnancy, ovarian cysts, and an ectopic pregnancy. A typical...

Latest answer posted November 30, 2021, 4:33 pm (UTC)

1 educator answer

Science

DNA is a double stranded helical structure. It is a polynucleotide made up of nitrogenous base pairs like adenine, guanine, cytosine, and thymine; phosphate group; and deoxyribose sugar. The...

Latest answer posted November 7, 2021, 11:37 am (UTC)

1 educator answer

Science

Gaseous exchange in an organisms follows these basic requirements: diffusible thin membrane, pressure gradient difference for the flow of gases, and exchange of gases in humans within the lungs....

Latest answer posted November 6, 2021, 1:54 pm (UTC)

1 educator answer

Science

Eukaryotic cells hold membrane-bound organelles and provide the foundation for organisms such as plants, animals, protozoa, and fungi. Inside a eukaryotic cell is an extensive compartmentalization...

Latest answer posted November 7, 2021, 11:48 am (UTC)

1 educator answer

Science

To help you get started on these questions, let's think about the consequences of introducing fungi or other plant pathogens into an ecosystem, how that happens, and how likely such an occurrence...

Latest answer posted December 2, 2021, 5:38 pm (UTC)

1 educator answer

Science

In the center of a herbaceous stem is a tissue known as pith or medulla. The pith is a soft, pale, whitish tissue with a spongy texture, made of parenchyma cells. It transports nutrients and water...

Latest answer posted December 2, 2021, 9:17 am (UTC)

1 educator answer

Science

Theoretical yield: "It is the maximum amount of product that can be formed in a reaction." Theoretical yield can be calculated using stoichiometric relation. If there are two reactants then it is...

Latest answer posted December 2, 2021, 3:26 am (UTC)

1 educator answer

Science

Several scientists were responsible for discovering radio waves and learning how to use them to send signals during the late 19th century and early 20th century. Some of the earliest credit goes to...

Latest answer posted November 24, 2021, 5:12 pm (UTC)

1 educator answer

Science

To design a study to evaluate the health impacts of PFAS (perfluoroalkyl and polyfluoroalkyl substances, or, as they are also known, "forever chemicals") in Long Island’s drinking water, consider...

Latest answer posted December 1, 2021, 12:50 am (UTC)

1 educator answer

Science

The electron arrangement talks about the distribution of electrons of an atom molecule or molecule in an atomic orbitals or molecular orbitals. Electrons are arranged in energy shells. 1) NF3...

Latest answer posted November 6, 2021, 2:22 pm (UTC)

1 educator answer

Science

The atom wasn't invented, it was discovered. Many Ancient Greek and Indian philosophers toyed with the idea that humans, animals, plants, objects, and everything else is made out of small...

Latest answer posted November 22, 2021, 3:39 pm (UTC)

1 educator answer

Science

Atoms are the most basic units of matter and all chemical elements. As everything in existence is made out of matter, everything is made out of atoms as well. The word atom comes from the Greek...

Latest answer posted November 22, 2021, 2:53 pm (UTC)

1 educator answer

Science

All the catalysts, enzymes affect the rate of reaction by lowering activation energy needed to initiate the reaction. An enzyme greatly reduces the activation energy (E`_a` ) necessary to initiate...

Latest answer posted November 9, 2021, 4:36 am (UTC)

1 educator answer

Science

Calcium (Ca) is a metal and belongs to Group 2 and Period 4 of the periodic table. It is an alkaline earth metal and has an atomic number of 20. Its electronic configuration can be written as: 1s2,...

Latest answer posted November 18, 2021, 4:17 am (UTC)

1 educator answer

Biology

Plasma is one of the main component of blood.The other components of blood are red blood cells, white blood cells and platelets. According to the composition of blood, plasma constitutes 55% of the...

Latest answer posted November 29, 2021, 9:23 am (UTC)

1 educator answer

Biology

The respiratory pigment in humans is Haemoglobin.It is a quaternary protein having 4 binding sites for oxygen. Hb has haeme protein with iron as a center. It has maximum binding capacity with...

Latest answer posted November 25, 2021, 6:55 am (UTC)

1 educator answer

Science

An atom is defined by the US Nuclear Regulatory Commission as "the basic building block of matter." Matter, or anything that occupies space, is made up of atoms. An atom is also the most basic unit...

Latest answer posted November 22, 2021, 11:17 pm (UTC)

1 educator answer

Science

Cellular respiration is a much more complex process that occurs inside the living cells. It is the oxidation of respiratory substrate(mainly glucose) in the cells resulting in the release of...

Latest answer posted November 6, 2021, 12:58 pm (UTC)

1 educator answer

Science

The prokaryotic cells are primitive non membrane bound structures, which includes bacteria, blue-green algae, mycoplasma, and PPLO (Pleuro Pneumonia Like Organisms). They are smaller in size and...

Latest answer posted November 8, 2021, 11:29 am (UTC)

1 educator answer

Science

Nerve cells, or neurons, are the structural and function units of nervous system. The nervous system is formed of millions of neurons. These receive, conduct, and respond to various stimuli....

Latest answer posted November 8, 2021, 11:57 am (UTC)

1 educator answer

Science

Facilitated diffusion is a type of passive transport. In living organisms, two types of transport systems are present. Passive transport and active transport, both help in transporting molecules...

Latest answer posted November 8, 2021, 12:20 pm (UTC)

1 educator answer

Science

By definition, an atom is the smallest component of an element having all the properties of that element. Atoms are the basic building block of all matter; everything is made up of atoms. Atoms are...

Latest answer posted November 23, 2021, 7:54 am (UTC)

1 educator answer

Science

Speciation is an evolutionary process by which new species arise. Inheritable variations are the cause as they keep accumulating from one generation to another. Speciation is the formation of one...

Latest answer posted November 10, 2021, 4:42 pm (UTC)

1 educator answer

Science

Neutrons are subatomic particles that, along with proteins, form the nucleus of every atom, except hydrogen. Unlike protons, which have a positive charge, and electrons, which have a negative...

Latest answer posted November 22, 2021, 5:59 pm (UTC)

1 educator answer

Science

In the scientific field of geology, a mineral is a naturally occurring, solid, and inorganic substance. Minerals have a defined chemical composition and an ordered internal structure. To be a...

Latest answer posted November 22, 2021, 6:15 pm (UTC)

1 educator answer

Science

Atoms are the basic element of all matter. The periodic table, which organizes atoms according to their atomic number (the amount of protons in the atom's nucleus), lists 118 known atoms. Atoms are...

Latest answer posted November 22, 2021, 4:22 pm (UTC)

1 educator answer

Science

An electron is a subatomic particle and is one of the components that constitute an atom of a chemical element. An electron has a negative charge. In comparison, a proton has a positive charge....

Latest answer posted November 22, 2021, 7:11 am (UTC)

1 educator answer

Science

An atom can be considered to be the smallest unit of any material. In other words, all the matter is made up of atoms. To be more accurate, atoms of a particular type constitute a chemical element....

Latest answer posted November 22, 2021, 7:03 am (UTC)

1 educator answer

Science

Oxidation number is defined as the residual charge on an atom in the combined state, or the charge on an atom in isolated state. It is the net charge an atom appears to have in the combined state....

Latest answer posted November 11, 2021, 4:55 pm (UTC)

1 educator answer

Science

In science, the term dilation (from the Latin word "dilatare," which means to expand) is used to describe the act of expansion or enlargement. It is present in several scientific fields. In...

Latest answer posted November 12, 2021, 8:36 am (UTC)

1 educator answer

Science

Formal charge is the charge present on an atom in a neutral or charged molecule. It can be defined as the difference in the valence electrons in an isolated neutral atom and electrons present on...

Latest answer posted November 17, 2021, 1:12 am (UTC)

1 educator answer

Science

Appositional growth is an expansion in width and/or diameter that occurs when more layers are added to a surface, making the surface thicker. The term appositional growth is generally used to refer...

Latest answer posted November 16, 2021, 4:57 pm (UTC)

1 educator answer

Science

An organ is a group of structurally similar tissues that carry out a particular function. Examples of organs found in animals are the heart, lungs, and kidneys. Examples of organs found in plants...

Latest answer posted November 6, 2021, 1:34 pm (UTC)

1 educator answer

Science

The charge of an element in a molecule can be determined by rules for oxidation number (O.N.) as follows: Element present in their natural state has O.N. zero like metals `Na, \ Mg,\ Ag,\ Fe \...

Latest answer posted November 18, 2021, 5:16 am (UTC)

1 educator answer

Science

Adult cisgender men generally speak with deeper voices than cisgender women because they have longer and thicker vocal cords. The development of these larger vocal cords, which are located inside...

Latest answer posted November 5, 2021, 7:16 pm (UTC)

1 educator answer

Science

The functional unit of a muscle cell is the sarcomere. Muscles work by contracting and relaxing. When a prime mover (muscle that is contracting) contracts it shortens and an opposing muscle...

Latest answer posted May 21, 2012, 10:42 am (UTC)

1 educator answer

Science

The phenomenon you are asking about is called refraction. Refraction is what happens to light as a result of traveling through a different medium, such as from air to water, or from air to...

Latest answer posted June 30, 2012, 5:45 pm (UTC)

1 educator answer

Science

Ionic bonding: a type of chemical bonding between the atoms of two different elements. The two elements are introduced to each other electrostatically, exchange electrons and become attracted,...

Latest answer posted June 23, 2012, 10:52 pm (UTC)

1 educator answer

Science

Hello! It is alkaline. The alkalinity of the solution is due to the capacity of the solution to neutralize acid. This happens when hydroxide content will increase. Apparently in this process we...

Latest answer posted October 17, 2012, 8:03 am (UTC)

1 educator answer

Science

The reaction above is called synthesis since two different substances combined to form one new substance. Its chemical equation has a form: `A + B -> AB` So when a carbon reacts with oxygen to...

Latest answer posted December 13, 2012, 1:37 am (UTC)

1 educator answer

Science

The number of white cells in the blood (WBC) is measured in the laboratory by a machine. The WBC count is part of a complete blood count (CBC), in which WBC and red cells (RBC) are counted....

Latest answer posted September 25, 2011, 6:36 am (UTC)

1 educator answer

Science

a phosphate group is a polyatomic ion which contains both ionic and covalent bonds. By definition, a phosphate group is PO4 with a charge of -3. The parent compound is phosphoric acid, H3PO4 which...

Latest answer posted June 21, 2011, 3:15 am (UTC)

1 educator answer

Science

First, lets make sure we understand the word "ratio". A ratio is a comparison of any two things, usually in numerical form. We could compare the number of boys in one of my classes to the number...

Latest answer posted June 26, 2012, 5:00 pm (UTC)

1 educator answer

Science

We have 2 grams of lead and 2 grams of iron. We need to figure out which contains more atoms. The number of atoms in a particular sample is easiest to find by working with moles. One mole of any...

Latest answer posted February 13, 2013, 12:11 am (UTC)

1 educator answer

Chemistry

A mole is just like saying you have a certain amount of something. When you say you have "ten" of something, it could be cats or atoms or pencils or ducks. You could say you have "ten thousand"...

Latest answer posted February 15, 2010, 12:17 pm (UTC)

1 educator answer

Chemistry

Methanamide (HCONH2) is also called formamide. The standard Lewis structure notation involves a single bond between the hydrogen and the carbon, a double bond between the carbon and the oxygen, a...

Latest answer posted November 18, 2012, 5:00 pm (UTC)

1 educator answer

Science

The life of a cell begins with its formation by cell division of a mother cell. The life ends with either the formation of daughter cells or by apoptosis. The sequential stages through which a cell...

Latest answer posted November 11, 2021, 3:20 am (UTC)

1 educator answer

Science

H2O2 + PbS --> PbSO4 + H2O Oxidation is the loss of electrons and reduction is the gaining of electrons. In an unofficial sense, the loss of oxygen is reduction and the gaining of oxygen is...

Latest answer posted December 13, 2012, 2:28 am (UTC)

1 educator answer

Science

This is an example of a physical change. Copper sulfate is a very hygroscopic material. This means that it absorbs and coordinates with water very readily. Note that this coordination with water...

Latest answer posted September 29, 2012, 3:38 pm (UTC)

1 educator answer

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