What is Plant Physiology? - Definition & Experiments

An error occurred trying to load this video.

Try refreshing the page, or contact customer support.

Coming up next: Adventitious Roots: Definition & Examples

You're on a roll. Keep up the good work!

Take Quiz Watch Next Lesson
Your next lesson will play in 10 seconds
  • 0:01 What Is Plant Physiology?
  • 0:25 Water Transport
  • 1:28 Nutrient Production &…
  • 2:18 Phototropism & Other Tropisms
  • 4:01 Fruit Ripening
  • 4:44 Lesson Summary
Save Save Save

Want to watch this again later?

Log in or sign up to add this lesson to a Custom Course.

Log in or Sign up

Speed Speed

Recommended Lessons and Courses for You

Lesson Transcript
Instructor: Amanda Robb

Amanda holds a Masters in Science from Tufts Medical School in Cellular and Molecular Physiology. She has taught high school Biology and Physics for 8 years.

Plants are enjoyed by many people - in our homes, on our tables as foods, and in hundreds of products we use every day. In this lesson, we will explore how plant physiology helps us to understand the many functions and behaviors of plants.

What Is Plant Physiology?

Plants have many different uses. But how do plants develop from seeds, and how do they grow? This is where plant physiology comes into play. Plant physiology is the study of how different parts of plants function. It includes many aspects of plant life, including nutrition, movement, and growth.

Water Transport

Water is an essential requirement for plant growth. Plants have a complex xylem system that moves water from the soil all the way up to the leaves, where it is used to make energy. The xylem moves water absorbed in the roots to the top of the plant through a process called transpiration. Water evaporates from the leaves, causing more water to flow upward to fill the gap. Think of it like a blood vessel system for the plant: The leaves act like the heart - a driving force moving water through the plant - and the xylem acts like the blood vessels. Properties of water, like adhesion and cohesion, where water sticks to itself and the xylem walls, helps the water to climb upward as well.

To really investigate the xylem, you can try this cool experiment at home. Mix some blue food coloring with water and place a stalk of celery (with leaves) in the solution. Within half an hour, the blue dye will climb through the xylem with the water and turn the leaves of the celery completely blue! That's the xylem in action.

Nutrient Production and Transportation

Plants also require nutrients to grow and develop, but unlike people, plants produce their own nutrients. All plant cells contain chlorophyll, a chemical which allows plants to harvest energy from the sun and create glucose (or sugar). The process by which plants make glucose is called photosynthesis. Glucose is the same sugar that is in foods like candy or bread. The entire plant needs this sugar, not just the green leaves, so plants have evolved a system called phloem to move the sugar and other nutrients to the entire plant. Phloem is similar to xylem in that it is a network of tubes within the plant designed to transport nutrients, but there is one big difference: Xylem flows in only one direction, like our blood, but phloem is more like our digestive system, distributing nutrients throughout the entire plant.

Phototropism and Other Tropisms

Scientist Charles Darwin and his son were the first to investigate phototropism in plants using the following experiment with grass seedlings. First, they cut off the tips of the shoots, and the plants did not grow towards the light. An opaque cap on the shoot also prevented light-directed growth, but a clear cap did not. In their conclusion, they reasoned that the indicator that causes phototropism was inside the tip of the shoot of the plant and was stimulated by light.

To unlock this lesson you must be a Study.com Member.
Create your account

Register to view this lesson

Are you a student or a teacher?

Unlock Your Education

See for yourself why 30 million people use Study.com

Become a Study.com member and start learning now.
Become a Member  Back
What teachers are saying about Study.com
Try it risk-free for 30 days

Earning College Credit

Did you know… We have over 200 college courses that prepare you to earn credit by exam that is accepted by over 1,500 colleges and universities. You can test out of the first two years of college and save thousands off your degree. Anyone can earn credit-by-exam regardless of age or education level.

To learn more, visit our Earning Credit Page

Transferring credit to the school of your choice

Not sure what college you want to attend yet? Study.com has thousands of articles about every imaginable degree, area of study and career path that can help you find the school that's right for you.

Create an account to start this course today
Try it risk-free for 30 days!
Create an account