1.3.1 The Need for Energy in Living Organisms

• Living organisms require energy to perform a variety of processes, including growth, movement, and homeostasis
• When ATP is broken down, it releases chemical energy that can be harnessed by cells to perform work
• What is the primary product of photosynthesis?

  Glucose
• Photosynthesis is the process by which plants and autotrophic bacteria convert light energy into chemical energy.
• Animals and heterotrophic bacteria obtain energy by consuming food.
• What is the definition of energy in living organisms?

  The capacity to do work
• Growth, movement, and homeostasis are all life processes that require energy.


  True
• Why are photosynthesis and the consumption of food both crucial for organisms?

  To provide energy
• Match the type of cellular respiration with its features:

  Aerobic respiration ↔️ Requires oxygen || Produces 36-38 ATP || Occurs in mitochondria

  Anaerobic respiration ↔️ Does not require oxygen || Produces 2 ATP || Occurs in cytoplasm
• What is energy defined as in living organisms?

  The capacity to do work
• What does ATP stand for?

  Adenosine Triphosphate
• Steps in the process of photosynthesis

  1️⃣ Sunlight is absorbed by chlorophyll

  2️⃣ Water is split into hydrogen and oxygen

  3️⃣ Carbon dioxide is fixed

  4️⃣ Glucose is produced
• What are the two primary methods by which organisms obtain energy?

  Photosynthesis and consumption of food
• What do plants use glucose for after it is produced during photosynthesis?

  Fueling life processes
• Match the energy acquisition method with its organisms, process, and products:

  Photosynthesis ↔️ Plants, autotrophic bacteria || Converts light energy into chemical energy || Glucose and oxygen

  Consumption of food ↔️ Animals, heterotrophic bacteria || Breaks down food through digestion || Glucose and other nutrients
• What happens when ATP is broken down in cells?

  Energy is released
• Animals and heterotrophic bacteria break down food through digestion.
• Where does cellular respiration occur in cells?

  Mitochondria
• Anaerobic respiration does not require oxygen and produces less ATP than aerobic respiration.


  True
• Growth requires energy from food to build new tissues.


  True
• Organisms obtain energy directly from the food they consume.

  True
• Animals obtain energy by consuming food
• During photosynthesis, plants use sunlight, water, and carbon dioxide to produce glucose and oxygen.


  True
• Digestion breaks down food to release glucose in animals and heterotrophic bacteria.

  True
• ATP is the main energy currency in living organisms.currency
• Steps involved in the photosynthesis process

  1️⃣ Light energy is absorbed by chlorophyll

  2️⃣ Water and carbon dioxide are used

  3️⃣ Glucose and oxygen are produced

  4️⃣ Glucose is stored for future use
• Aerobic respiration requires oxygen and produces a large amount of ATP.