How Organisms Obtain Energy Section 8.1 Pg

What is energy? Energy is the ability to do work!

Thermodynamics Thermodynamics is the study of the flow and transformation of energy in the universe. 2 Laws! First law — energy can be converted from one form to another, but it cannot be created nor destroyed. Second law — energy cannot be converted without the loss of usable energy.

How do you get your energy? >All living organisms depend on energy. >All cells need chemical energy. This energy comes from food. >Molecules in food store chemical energy in their bonds.

Autotrophs and Heterotrophs Organisms, such as plants, which make their own food, are called autotrophs. Organisms, such as animals, that must obtain energy from the foods they consume are heterotrophs.

Metabolism All the chemical reactions in a cell is referred to as the cells metabolism. Our cells get most of the energy needed for metabolism from the food we eat The chemical energy used for most cell processes is carried by ATP. Brainpop

Metabolic pathways Catabolic-release energy by breaking down large molecules into small ones Anabolic- use energy to build large molecules from small molecules.

2 Main Energy Pathways that we are going to learn. 1.Photosynthesis 2.Cellular respiration

Photosynthesis Photosynthesis—light energy from the Sun is converted to chemical energy for use by the cell Is this Catabolic or Anabolic?

Cellular respiration Cellular respiration—organic molecules are broken down to release energy for use by the cell Is this Catabolic or Anabolic?

Compare the two Formulas Photosynthesis Cellular respiration

?Confused? Don’t worry we will talk more about these two processes in 8.2 and 8.3. The main thing to understand today is this idea of energy

Energy comes in many forms including light, heat, and electricity. In the body, energy can be stored in chemical compounds, too. The chemical energy used for most cell processes is carried by ATP ATP = ENERGY!!!

ATP An important chemical compound that cells use to store and release energy is adenosine triphosphate, abbreviated ATP. ATP is used by all types of cells as their basic energy source.

ATP consists of 3 parts: o adenine o ribose (a 5-carbon sugar) o 3 phosphate groups

Mr. Harry Styles

What does Mr. Harry Need? Needs

= Lots of ADP

ATP-ADP

Adenosine triphosphate (ATP) is the energy molecule of cells. The energy of ATP is stored in the phosphate bonds. When the bond between phosphates is broken, energy is released: AdenosinePPP PP P + energy P (ATP) (ADP) ATP/ADP Cycle This creates adenosine diphosphate (ADP), which is most abundant in the cell. AdenosinePPP

Storing Energy ADP or adenosine diphosphate has two phosphate groups instead of three. A cell can store small amounts of energy by adding a phosphate group to ADP

Releasing Energy Energy stored in ATP is released by breaking the chemical bond between the second and third phosphates.

The role of ATP The energy from ATP is needed for many cellular activities, including active transport across cell membranes, protein synthesis and muscle contraction. ATP’s characteristics make it exceptionally useful as the basic energy source of all cells. This is why ATP is known as the energy currency of the cell!! ATP

Which law of thermodynamics explains why the ladybug receives the least amount of usable energy? Cellular Energy 8.1 Formative Questions Chapter 8

True or False All of the energy from the food you eat comes from the sun. Cellular Energy 8.1 Formative Questions Chapter 8

Why is cellular respiration a catabolic pathway? Cellular Energy 8.1 Formative Questions A. Energy is used to form glucose and oxygen. B. Energy is converted from water to carbon dioxide. C. Energy that is lost is converted to thermal energy. D. Energy is released by the breakdown of molecules. Chapter 8

A. It captures light energy from the sun. B. It is produced in anabolic pathways. C. It stores and releases chemical energy. Why is adenosine triphosphate (ATP) such an important biological molecule? Cellular Energy 8.1 Formative Questions D. It converts mechanical energy to thermal energy. Chapter 8