DNA and Genes

DNA and Genes

DNA is an essential molecule for life. It acts like a recipe holding the instructions telling our bodies how to develop and function. 

What does DNA stand for? 

DNA is short for deoxyribonucleic acid. 

What is DNA made of? 

DNA is a long thin molecule made up of something called nucleotides. There are four different types of nucleotides: adenine, thymine, cytosine, and guanine. They are usually represented by their first letter:

• A- adenine
• T- thymine
• C - cytosine
• G - guanine

Holding the nucleotides together is a backbone made of phosphate and deoxyribose. The nucleotides are sometimes referred to as "bases". 

The basic structure of the DNA molecule

Different Cells in the Body 

Our bodies have around 210 different types of cells. Each cell does a different job to help our body to function. There are blood cells, bone cells, and cells that make our muscles. 

How do cells know what to do? 

Cells get their instructions on what do to from DNA. DNA acts sort of like a computer program. The cell is the computer or the hardware and the DNA is the program or code. 

The DNA Code 

The DNA code is held by the different letters of the nucleotides. As the cell "reads" the instructions on the DNA the different letters represent instructions. Every three letters makes up a word called a codon. A string of codons may look like this: 

ATC TGA GGA AAT GAC CAG

Even though there are only four different letters, DNA molecules are thousands of letters long. This allows for billions and billions of different combinations. 

Genes 

Within each string of DNA are sets of instructions called genes. A gene tells a cell how to make a specific protein. Proteins are used by the cell to perform certain functions, to grow, and to survive. 

Shape of the DNA Molecule 

Although DNA looks like very thin long strings under a microscope, it turns out that DNA has a specific shape. This shape is called a double helix. On the outside of the double helix is the backbone which holds the DNA together. There are two sets of backbones that twist together. Between the backbones are the nucleotides represented by the letters A, T, C, and G. A different nucleotide connects to each backbone and then connects to another nucleotide in the center. 

Only certain sets of nucleotides can fit together. You can think of them like puzzle pieces: A only connects with T and G only connects with C. 

Interesting Facts about DNA

• About 99.9 percent of the DNA of every person on the planet is exactly the same. It's that 0.1 percent that is different that makes us all unique.
• The double helix structure of DNA was discovered by Dr. James Watson and Francis Crick in 1953.
• If you unraveled all the DNA molecules in your body and placed them end to end, it would stretch to the Sun and back several times.
• DNA is organized into structures called chromosomes within the cell.
• DNA was first isolated and identified by Swiss biologist Friedrich Meischer in 1869.

http://www.ducksters.com/science/biology/dna.php

Animal (Classification) Song

Types of Microorganisms

http://chaucp.blogspot.com.br/2012/11/types-of-microorganisms.html

Class Discussion

In your blog book copy and answer these questions.

1.Which of the following is a NOT a micro-organism, but helps bread rise in baking?

2.What do people have in common with single-celled organisms?


3.Illustrate and label parts of a paramecium. Use your science book to help you.(Page A16)

4.What structure does the paramecium use to move?

YEAST

Yeast, a microscopic, one-celled organism belonging to the group of organisms called fungi. There are many kinds of yeasts, some of them of great importance to humans. 

Yeast is necessary to make leavened bread, beer, cheese, wine, and whiskey. It is rich in B vitamins; a form of yeast called brewer's yeast is used as a diet supplement. Yeast is also used in genetic engineering to produce large quantities of certain hormones and enzymes, which are used for such medical purposes as healing wounds and reducing inflammation. Some types of yeast, however, cause disease; candidiasis, a skin infection, is an example.
Yeasts are found in the soil, in water, on the surface of plants, and on the skin of humans and other animals. Like other fungi, yeasts obtain food from the organic matter around them; they secrete enzymes that break down the organic matter into nutrients they can absorb.
The yeast cell is oval or round and has a thin membrane. Under ideal conditions of moisture, temperature, and food supply, it reproduces asexually, by budding. When a yeast cell reaches full growth, a budlike swelling forms on its surface. Part of the parent cell's nucleus goes into this bud, and a wall is formed between the parent cell and the bud, which then becomes a separate cell. This new cell may break off when it is full grown. It may, however, remain attached as it produces another bud. In this way, chains or clusters of cells are formed. Budding is a rapid process, requiring about 20 minutes to produce a new organism.

http://science.howstuffworks.com/life/fungi/yeast-info.htm

What is a tissue?

A doctor does not work alone. He or she works with other doctors, nurses and medical staff to make people healthy. A builder does not work alone. There are other builders who help do the same job. Likewise, most cells do not work alone. They work with other similar cells to form what is called a tissue.
A tissue is a group of similar cells that all work together on the same job. For example, tissues in your lungs are made up of millions of similar cells working together to transport oxygen to the blood. Blood itself is a liquid tissue that transports oxygen, food and waste throughout the body.

Different types of tissues come together to form organs. For example, the heart is an organ made up of muscle tissue, blood tissue, and nerve tissue. An organ has an important job that keeps the living thing alive.

Like animals, plants also have organs. Common plant organs are leaves, stems and roots.

http://www.kidsbiology.com/biology_basics/cells_tissues_organs/structure_of_living_things2.php

Cell Organizationg

google images

Study Sites

Some great sites to help you learn more about cells.

http://www.kidsbiology.com/biology_basics/cells_tissues_organs/structure_of_living_things1.php

http://www.wisc-online.com/Objects/ViewObject.aspx?ID=AP11403

Label the plant/animal cells.

http://www.sheppardsoftware.com/health/anatomy/cell/plant_cell_game.htm


http://www.sheppardsoftware.com/health/anatomy/cell/index.htm

http://www.curriculumbits.com/prodimages/details/biology/label-the-cells.html

http://www.purposegames.com/game/label-the-plant-cell-quiz

Plant vs Animal Cells

https://sites.google.com/site/tabraham4/cells

Animal Cell

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

vb

 

 http://www.enchantedlearning.com/subjects/animals/cell/

 The following is a glossary of animal cell terms:
cell membrane - the thin layer of protein and fat that surrounds the cell. The cell membrane is semipermeable, allowing some substances to pass into the cell and blocking others.
centrosome - (also called the "microtubule organizing center") a small body located near the nucleus - it has a dense center and radiating tubules. The centrosomes is where microtubules are made. During cell division (mitosis), the centrosome divides and the two parts move to opposite sides of the dividing cell. The centriole is the dense center of the centrosome.
cytoplasm - the jellylike material outside the cell nucleus in which the organelles are located.
Golgi body - (also called the Golgi apparatus or golgi complex) a flattened, layered, sac-like organelle that looks like a stack of pancakes and is located near the nucleus. It produces the membranes that surround the lysosomes. The Golgi body packages proteins and carbohydrates into membrane-bound vesicles for "export" from the cell.
lysosome - (also called cell vesicles) round organelles surrounded by a membrane and containing digestive enzymes. This is where the digestion of cell nutrients takes place.
mitochondrion - spherical to rod-shaped organelles with a double membrane. The inner membrane is infolded many times, forming a series of projections (called cristae). The mitochondrion converts the energy stored in glucose into ATP (adenosine triphosphate) for the cell.
nuclear membrane - the membrane that surrounds the nucleus.
nucleolus - an organelle within the nucleus - it is where ribosomal RNA is produced. Some cells have more than one nucleolus.
nucleus - spherical body containing many organelles, including the nucleolus. The nucleus controls many of the functions of the cell (by controlling protein synthesis) and contains DNA (in chromosomes). The nucleus is surrounded by the nuclear membrane.
ribosome - small organelles composed of RNA-rich cytoplasmic granules that are sites of protein synthesis.
rough endoplasmic reticulum - (rough ER) a vast system of interconnected, membranous, infolded and convoluted sacks that are located in the cell's cytoplasm (the ER is continuous with the outer nuclear membrane). Rough ER is covered with ribosomes that give it a rough appearance. Rough ER transports materials through the cell and produces proteins in sacks called cisternae (which are sent to the Golgi body, or inserted into the cell membrane).
smooth endoplasmic reticulum - (smooth ER) a vast system of interconnected, membranous, infolded and convoluted tubes that are located in the cell's cytoplasm (the ER is continuous with the outer nuclear membrane). The space within the ER is called the ER lumen. Smooth ER transports materials through the cell. It contains enzymes and produces and digests lipids (fats) and membrane proteins; smooth ER buds off from rough ER, moving the newly-made proteins and lipids to the Golgi body, lysosomes, and membranes.
vacuole - fluid-filled, membrane-surrounded cavities inside a cell. The vacuole fills with food being digested and waste material that is on its way out of the cell.

Plant Cell

Cell Wall -

Function: Maintain cell pressure and prevent over-expansion of cells

 

Cell Membrane-

Function: Protects the cell from surrounding

 

Chloroplast-Found only in plants
Function: Conducts photosynthesis

 

Cytoplasm -

Function: Site of multiple cell processes including, cell metabolism

 

Golgi Body/apparatus -
Function: Sorting, processing and modifying proteins

 

 

Lysosomes-

Rare in plant cells.

Function:help bbreak down nutrients and old cell parts.

 

 

Mitochondrion-

Known to be the 'power house' or the 'storehouse of energy' of the cell, the mitochondria plays an important role in a cell.
Function: Energy production and conversion, regulates cell metabolism

 

Nucleus -

Function: Controls expression and transcription of the gene

 

Peroxisomes -

Membrane-bound packets of oxidative enzymes, the peroxisomes play a vital role in converting fatty acids to sugar. They also assist the chloroplasts in photo-respiration. Their functions include the glyoxylate cycle that occurs in germinating seeds and photo-respiration in leaves.

Function: Breakdown of metabolic hydrogen peroxide

 

Ribosomes-

Function: Protein builders and synthesizers

 

Smooth Endoplasmic Reticulum-

Similar to the structure of the rough ER, the smooth ER is a separate interconnected network membrane structure that is free from ribosomes. The SER transports material through the cell. It is also crucial in producing and digesting lipids and proteins.

Function: Manufactures and transports lipids

 

Vacuole- 

One large central vacuole.
Function: Regulates internal environment

 

http://www.buzzle.com/articles/labeled-plant-cell-diagram-and-functions.html

 

 

 

 

http://www.buzzle.com/articles/labeled-plant-cell-diagram-and-functions.html

Cells to Systems

http://www.livebinders.com/play/play?id=46976

Cells Are So Clever

Earth day 2013 The Face of Climate Change

The Face of Climate Change

Climate change can seem like a remote problem for our leaders, but the fact is that it's already impacting real people, animals, and beloved places. These Faces of Climate Change are multiplying every day.

What A Wonderful World With David Attenborough -- BBC One [FULL HD]

What causes the seasons?

What causes the seasons?
The seasons are caused by the tilt of the Earth's rotational axis away or toward the sun as it travels through its year-long path around the sun. The Earth has a tilt of 23.5 degrees relative to the "ecliptic plane" (the imaginary surface formed by it's almost-cicular path around the sun). The tilt toward the sun is maximized during Northern Hemisphere summer in late June (the "summer solstice"). At this time, the amount of sunlight reaching the Northern Hemisphere is at a maximum. In late December, on the date of the "winter solstice", the Earth's tilt away from the sun is maximized, leading to a minimum of sunlight reaching the Northern Hemisphere. The seasons, of course, are reversed in the Southern Hemisphere. During the winter, cold air masses build up over North America, Europe, and Asia, due to the low intensity of sunlight. The oceanic air masses are much less affected by the seasons because circulations in the upper ocean replenish warm surface water if it has been cooled. The strong temperature contrast between the cold air masses over land and the relatively warmer air masses over the ocean lead to extratropical (non-tropical) cyclone formation (low pressure). These storms are thus much more frequent and intense in the winter than in the summer.
Interesting facts:
The sun is actually closest to the Earth during Northern Hemisphere winter (not summer). Thus, the amount of sunlight averaged over the whole Earth, is as much as 7% more intense in the winter than the summer. Despite this fact, the global-average surface temperature is warmer in Northern Hemisphere summer, due to the much greater expanse of land there, and since land heats to a higher temperature than the ocean does.
http://www.weatherquestions.com/What_causes_the_seasons.htm

What Causes Earth's Seasons?

The Water Cycle

  We are going to explain about the water cycle: evaporation, transpiration, condensation, precipitation, runoff and collection.

    Evaporation is when the sun heats up the water in rivers, lakes or the oceans. It transforms into steam or vapor. The steam or vapor goes in to the air. Transpiration is when the plants give off a little bit of water vapor.

 Water vapor in the air gets very cold and changes back in to liquid. The water vapor condenses and forms clouds.

 Precipitation occurs when there is a lot of water condensed, and the clouds are full of water and can’t hold any more the water. The clouds get heavy and it can rain or snow.

 Runoff is the movement of land water to the oceans mainly in the forms of rivers, lakes and streams.

 Collection is when the water falls back to earth as precipitation, it may fall back in the oceans, lakes or rivers or it may end up on land. When it ends up on land, it will either soak into the earth as ground water or it may run over the soil and collect in rivers, lakes or oceans.

Water is in a constantly moving cycle and heat is the key to how this happens. Water changes its form as it is heated or cooled. When it is heated it turns to steam or vapor and when it is cooled it turns back to a liquid or into solid ice.

We study allot to write this text.  We hope you enjoy our presentation!

Daniel,Juliana,Catarina,Paul