Honors Biology- Unit 3

What happens to energy when bounds are formed?

Energy is being used to make the bound and keep the substances together.

What happens to energy when bounds are broken?

Energy is made

What is the overall function of an enzyme in cellular respiration and photosynthesis? 

The main function is to act like a biological catalyst that accelerates the complex chemical reactions by lowering the activation energy required for them to proceed. 

What are the five factor that affect the rate of a chemical reaction?

temperature, concentration of reactants, surface area of solid reactants, presence of a catalyst, and the nature of the reactants.  

What is metabolism?

All of the chemical reactions within each cell of an organism. It provides energy for life's processes and creates key molecules

What are chemical reactions?

a process where existing chemical bonds break and new ones form, leading to the transformation of initial substances (reactants) into different substances (products) with altered chemical compositions and properties

What is a catabolic reaction?

Breaks down larger molecules into simpler compounds. It is a release of energy which equals exergonic 

What is a anaboloic reaction?

Builds larger molecules to form smaller ones. Requires consuming energy to do it which equals endergonic

What is activation energy?

The amount of energy needed to make a chemical reaction start

What is a reactant (substrate)?

Substances that are changed during a chemical reaction 

What is a product?

Substances that are made by a chemical reaction

What is endothermic?

Absorbs energy in the form of light and heat

What is exothermic?

Releases energy in the form of light or heat.

What is an enzyme?

Mostly proteins that speed up biochemical reactions by lowering the activation energy.

What is a catalyst?

substances that speed up reactions without being permanently altered

What is the active site?

The place where the enzyme meets the substrate

What is denaturation?

enzymes active site gets deformed and losses it specific shape and loss of biological activity. This is caused by environment changes like: extreme changes in pH, temperature, iron strength, and solubility.

What does ATP stand for?

Adenosine Triphosphate

What is the purpose of ATP?

to serve as the universal "energy currency" of the cell, providing the readily usable energy needed for virtually all cellular activities, such as muscle contraction, nerve impulse propagation, and the synthesis of proteins and DNA

Describe the APT-ADP cycle and what is recycled and what is not

The ATP-ADP cycle is the constant interconversion of adenosine triphosphate (ATP) and adenosine diphosphate (ADP) to provide usable energy for cells. When ATP is used, it breaks into ADP and an inorganic phosphate group (Pi), releasing energy for cellular work. The ADP and Pi are then recycled when new energy, derived from nutrients via cellular respiration, reattaches them to form ATP again. The energy released from ATP hydrolysis is not recycled but is used to power cellular activities, while the inorganic phosphate is recycled within the cycle

Explain what the energy is used for when a phosphate is removed, and where that energy initially comes from.

When a phosphate is removed from ATP (adenosine triphosphate) through a process called hydrolysis, the released energy is used to power cellular processes like muscle contraction, active transport, and biochemical reactions. The energy initially comes from the breakdown of food molecules, such as glucose, during cellular respiration

Summarize why the overall process of breaking down ATP is considered an exothermic process, while the overall process of forming ATP is considered an endothermic process.

Breaking down ATP is exothermic because the repulsion of its negative phosphate groups and the formation of stable, lower-energy products (ADP and Pi) results in a net release of usable energy. In contrast, forming ATP is endothermic, requiring an input of energy from sources like cellular respiration to force ADP and Pi together against this repulsion, creating a higher-energy, less stable molecule to store energy.  

What is ATP?

the principal energy currency used by cells to power biological processes

What is chemiosmosis

the process in cells where energy from an ion gradient, most often a proton (H+) gradient, is used to create ATP, the cell's primary energy currency

What is photosynthesis?

The process used by plants, algae, and some bacteria to convert light energy into chemical energy to produce food for themselves and oxygen as a byproduct. 

What is the stroma?

The fluid-filled space around the thylakoids that is the sight for the light-independent reactions.