Photosynthesis

Elodea Experiment

• In this experiment we will explore what is known as plant pearling, a process that occurs in aquatic plant species as a result of photosynthesis.

• Plant pearling is when bubbles of oxygen accumulate on the leaves of plants and sometimes float to the top of the aquarium like in a glass of campaign.

• It’s a sign that you have a healthy environment in your aquarium.

Elodea Experiment

• http://youtu.be/40Zwv1oxAXU• Elodea Experiment

Photosynthesis

• Photosynthesis is the process by which a cell captures energy and uses it to make food.

• Almost all living things obtain energy either directly or indirectly from the energy of sunlight that is captured during photosynthesis.

Photosynthesis

• Plants make their own food through the process of photosynthesis.

• An organism that makes its own food is called an autotroph.

Photosynthesis

• http://www.neok12.com/php/watch.php?v=zX4b7a504d047d5b6e660173&t=Photosynthesis

Photosynthesis

• An organism that cannot make its own food is called a heterotroph.

• Many heterotrophs obtain food by eating other organisms.

Photosynthesis

• During photosynthesis, plants and some other organisms absorb energy from the sun and use the energy to convert carbon dioxide and water into sugars and oxygen.

Photosynthesis

• Photosynthesis occurs mostly in the leaves of plants where the chloroplasts, green organelles in plant cells are.

• Chlorophyll is a pigment in chloroplasts that is responsible for photosynthesis.

Photosynthesis

• During stage 1, water in the chloroplasts is split into hydrogen and oxygen.

• The oxygen is given off as a waste product as seen in aquatic plants undergoing the process of pearling.

• The oxygen exits the leaf through openings on its underside.

Photosynthesis• During Stage 2 of

photosynthesis cells use the hydrogen that was split off from the water, energy from the sun, and the carbon dioxide from the air to produce sugars.

• Some of these sugars are used to give plants energy while others are stored.

Cellular Respiration• During cellular

respiration, cells break down glucose and other molecules from food in the presence of oxygen to release energy.

• Breathing removes the waste product of cellular respiration (carbon dioxide) from your body.

Cellular Respiration

• During the first stage of cellular respiration the molecule of glucose (the sugar) is broken down in the cytoplasm of the cell.

• Then, in the second stage, oxygen is used to break down molecules even more to produce energy.

• The second stage of cellular respiration occurs in the mitochondria, the powerhouse of the cell.

Powering the Cell: Mitochondria

• This is what it looks like inside of your cell as cellular respiration is occurring right now.

• http://youtu.be/RrS2uROUjK4

Comparing Cellular Respiration and Photosynthesis

Fermentation

• Some organisms can live in the absence of oxygen through a process called fermentation.

• Fermentation is an process in which cells release energy from food without using oxygen.

• Making cheese is a process that uses fermentation

• http://youtu.be/776I-YD6jDo

Fermentation• Alcoholic fermentation is a

type of fermentation that occurs in yeast and other single-celled organisms.

• It produces alcohol, carbon dioxide and some energy.

• Bakers and brewers use yeast to make bread rise and drinks sparkle.

Fermentation

• What evidence can you see of a product of alcoholic fermentation in this picture?

Fermentation

• Lactic Acid Fermentation occurs in your muscles when you exercise when your muscle cells use oxygen faster than it can be replaced.

• A product of this type of fermentation is lactic acid.

Fermentation

• When lactic acid builds up in your muscles, your muscles feel weak and sore.

• Later, when your cells get more oxygen, the lactic acid will break down and the pain will go away.