Exercise A Your Piece of the

All organisms function by using and processing energy. Energy enters the web of life via photosyndicsis, is stored in biomass, and is released by cellular respiration (see Laboratory Topic 5). As a living being, you arc dependent on a continual inflow of energy. Since humans arc not capablc of photosynthesis, we must get all our energy from the food we eat. Where did the energy in our food come from? Ultimately it came from the sun.

The objective of this excrcisc is for you to get a sense for "your piece of the sun." In other words, we will calculate the amount of energy needed to support you as an organism, in particular, a normal consumer of the early tw enty-first century. By keeping track of your f<xxl consumption, you will estimate how much energy you consume in an average year. Then, based on what you typically cat, we will build your personal food web (fig. 10.1). You will be able to account for the energy as it flows from the sun, through other organisms, and finally to you. You will sec the connections between you and the other plants and animals needed to provide your food. If you lived like other animals, this food web would be adequate to describe all die energy inputs needed to meet your metabolic needs. However, modern humans are different from other organisms. We use additional sources of energy for cooking, processing, transporting, refrigerating, fertilizing, and cultivating our food. You will estimate some of these additional subsidies and add them to your total energy consumption. Sincc most of this added energy comes from fossil fuels, it can be considered "your piecc of the past."

It is so easy to go to the grocery store or visit your favorite fast-food restaurant diat many of us have lost touch with the agricultural system that helps provide our food. In this exercise, you will connect the food you eat with the bigger picture.

Total Solar Energy

(nooded to support you)

Solar onoKjy reflocted or remdintQ<i

(23) ioa kcal yr1

10* kcal yr

Plant crops: Gross production

Plant respiration

Your consumplion of plants

Crops led to livestock Gross production

_ 106 kcal yr1

Livestock: Gross energy Intake

Your consumption o( meat nn<l dairy products (6) 10r' kcal yr1

Plant rosplration

Animal respiration

Phytoplnnkton: Gross production

If^iish & shellfish: Gross onorgy Intako

  • 19) I06 kcal yr1
  • 7 x"

Your consumption ol fish & shollflsh

106 kcal yr1

n you

Your gross onorgy intako (1) 10° kcal yr'

Rosplration and other losses (21) to"kcal yr1

Fish respiration

Your BMR

Energy activity onorgy

Digestion and wasto

Was this article helpful?

0 0
Building Your Own Greenhouse

Building Your Own Greenhouse

You Might Just End Up Spending More Time In Planning Your Greenhouse Than Your Home Don’t Blame Us If Your Wife Gets Mad. Don't Be A Conventional Greenhouse Dreamer! Come Out Of The Mould, Build Your Own And Let Your Greenhouse Give A Better Yield Than Any Other In Town! Discover How You Can Start Your Own Greenhouse With Healthier Plants… Anytime Of The Year!

Get My Free Ebook


Post a comment