Genes in America

Hi its me Naika from NY! Im here to tell you what another school is doing while your with your experiments. We're studing genes over here, and we've seen dominant and recessive genes and punnet squares and how to use them and figure out what genes the offspring could have. We're going to watch a national geografic video on sexual reproduction (after the school finishes editing it!).

Chemical Reaction

A chemical reaction is a process that results in the interconversion of chemical substances . The substance or substances initially involved in a chemical reaction are called reactants. Chemical reactions are characterized by a chemical change, and they yield one or more products which are, in general, different from the reactants. Classically, chemical reactions encompass changes that strictly involve the motion of electrons in the forming and breaking of chemical bonds, although the general concept of a chemical reaction, in particular the notion of a chemical equation, is applicable to transformations of elementary particles, as well as nuclear reactions. On the classical definition, therefore, there are only two types of chemical reaction: redox reactions and acid-base reactions. The former involve the motion of lone electrons and the latter of an electron pair.

Different chemical reactions are used in combinations in chemical synthesis in order to get a desired product. In biochemistry, series of chemical reactions form metabolic pathways, since straight synthesis of a product would be energetically impossible in conditions within a cell. Chemical reactions are also divided into organic reactions and inorganic reactions.

Some reaction are:

• Isomerisation, in which a chemical compound undergoes a structural rearrangement without any change in its net atomic composition; see stereoisomerism
• Direct combination or synthesis, in which two or more chemical elements or compounds unite to form a more complex product:

N₂ + 3H₂ → 2NH₃

• Chemical decomposition or analysis, in which a compound is decomposed into smaller compounds or elements:

2H₂O → 2H₂ + O₂

• Single displacement or substitution, characterized by an element being displaced out of a compound by a more reactive element:

2Na + 2HCl → 2NaCl + H₂

• Double displacement or coupling substitution , in which two compounds in aqueous solution (usually ionic) exchange elements or ions to form different compounds:

NaCl + AgNO₃ → NaNO₃ + AgCl

• Combustion, in which any combustible substance combines with an oxidizing element, usually oxygen, to generate heat and form oxidized products. The term combustion is used usually only large-scale oxidation of whole molecules, i.e. a controlled oxidation of a single functional group is not combustion.

C₁₀H₈+ 12O₂ → 10CO₂ + 4H₂O

CH₂S + 6F₂ → CF₄ + 2 HF + SF₆

DNA

Deoxyribonucleic acid (DNA) is a nucleic acid that contains the genetic instructions for the development and functioning of living organisms. All living things contain DNA genomes. A possible exception is a group of viruses that have RNA genomes, but viruses are not normally considered living organisms. The main role of DNA in the cell is the long-term storage of information. The genome is often compared to a set of blueprints, since it contains the instructions to construct other components of the cell, such as proteins and RNA molecules. The DNA segments that carry this genetic information are called genes, but other DNA sequences have structural purposes, or are involved in regulating the expression of genetic information.

In eukaryotes such as animals and plants, DNA is stored inside the cell nucleus, while in prokaryotes such as bacteria, the DNA is in the cell's cytoplasm. Unlike enzymes, DNA does not participate directly in most of the biochemical reactions it controls; rather, various enzymes act on DNA and copy its information into either more DNA, in DNA replication, or transcribe and translate it into protein. In chromosomes, chromatin proteins such as histones compact and organize DNA, which helps control its interactions with other proteins in the nucleus.

DNA is a long polymer of simple units called nucleotides, which are held together by a backbone made of sugars and phosphate groups. This backbone carries four types of molecules called bases, and it is the sequence of these four bases that encodes information. The major function of DNA is to encode the sequence of amino acid residues in proteins, using the genetic code. To read the genetic code, cells make a copy of a stretch of DNA in the nucleic acid RNA. Some RNA copies are used to direct protein biosynthesis, but others are used directly as parts of ribosomes or spliceosomes.

Animal Cell

An animal cell is a form of eukaryotic cell which make up many tissues in animals. The animal cell is distinct from other eukaryotes, most notably plant cells, as they lack cell walls and chloroplasts, and they have smaller vacuoles. Due to the lack of a rigid cell wall, animal cells appear to be circular (though are often deformed by surrounding cells) under microscopes - in three dimensions the cells are normally spherical. Human cells are biologically categorized as animal cells.

Cytoplasm
All cells consist of a jelly-like substance called Cytoplasm.The cytoplasm allows substances such as food and oxygen to move around within the cell take place in a cytoplasm .

Cell membrane
Surrounding the cytoplasm is a soft and thin cell membrane.The cell membrane holds the cytoplasm inside it. It also controls substances that go in or out of the cell.

Nucleus
In both plant and animal cells, there is a nucleus found in the cytoplasm. The nucleus is a very important part of a cell. It controls everything that happens inside the cell.

Comets

A comet is a small body in the solar system that orbits the Sun and (at least occasionally) exhibits a coma (or atmosphere) and/or a tail — both primarily from the effects of solar radiation upon the comet's nucleus, which itself is a minor body composed of rock, dust, and ice. Comets' orbits are constantly changing: their origins are in the outer solar system, and they have a propensity to be highly affected (or perturbed) by relatively close approaches to the major planets. Some are moved into sungrazing orbits that destroy the comets when they near the Sun, while others are thrown out of the solar system forever.

Comets are usually discovered visually or photographically using a wide-field telescope or other optical means of magnification, such as binoculars. However, even without access to optical equipment, it is still possible to discover a sungrazing comet online with a computer and an Internet connection.

Most comets are believed to originate in a cloud (the Oort cloud) at large distances from the Sun consisting of debris left over from the condensation of the solar nebula; the outer edges of such nebulae are cool enough that water exists in a solid (rather than gaseous) state. Asteroids originate via a different process, but very old comets which have lost all their volatile materials may come to resemble asteroids.

Electron Microscopes

Electron microscopes, which use beams of electrons instead of light, are designed for very high magnification usage. Electrons, which have a much smaller wavelength than visible light, allow a much higher resolution. The main limitation of the electron beam is that it must pass through a vacuum as air molecules would otherwise scatter the beam.
Instead of relying on refraction, lenses for electron microscopes are specially designed electromagnets which generates magnetic fields that are approximately parallel to the direction that electrons travel. The electrons are typically detected by a phosphor screen, photographic film or a CCD.

Two major variants of electron microscopes exist:

Scanning electron microscope: looks at the surface of bulk objects by scanning the surface with a fine electron beam and measuring reflection. May also be used for spectroscopy.
Transmission electron microscope: passes electrons completely through the sample, analogous to basic optical microscopy. This requires careful sample preparation, since electrons are scattered so strongly by most materials. It can also obtain detailed information on the sample's crystallography through selected area diffraction.

Virtual Lab

NASA has done a program which can be downloaded by clicking here. This program is called Virtual Lab, and consists of downloadable images taken with powerfull microscopes. There are alot of strange images you can download, as a water beetle.

Did you know?

ph really means "power of hydrogen". This is used to measure acidity or alkalinity( I suppose you already know this part). There is two ways of calculating the ph of a substance:

1. With a complicated equation:

or

2. With universal indicators like: red cabbage, litmus paper, phenolphthalein, methyl orange, phenol red, bromothymol blue, and bromocresol purple.

Another example of universal indicator is the plant Hydrangea macrophylla, which flowers change of colour depending of the pH of the soil (acid soil=blue flowers, alkaline soil=pink flowers)

(All links go to Wikipedia)

See you!

Im new!

Im Nicolas, and I will be showing what we do in new york, caneticut. I will post as soon as I can, assuming that they don't give too much homework there!