Chapter 5 Flashcards
What do algae, Cyanobacteria, and plants have in common?
They are all photosynthetic-that is, they carry out photosynthesis, using the energy from sunlight and carbon dioxide from air to synthesize sugars
Can animals directly use the energy of sunlight to make their own food(in their own bodies)
No
What organelles would a nonphotosynthetic alga need to be able to carry out photosynthesis
Chloroplast
Why do many species of algae appear green?
The main photosynthetic pigment is chlorophyll, which reflects green wavelengths
Compare and contrast the ways photosynthetic algae and animals obtain and use energy
Photosynthetic algae rely on photosynthesis for the production of sugars that can be used for short-term energy needs or for longer term energy storage. Animals cannot make their own sugars from scratch, so must obtain them from their diet.
Hat would happen to humans and other animals if algae, Cyanobacteria, and plants were wiped out? Would we only lose a good source (e.g. Plants), or would there be other repercussions?
There would be several repercussions for humans if photosynthetic organisms were wiped out. First, critical food and energy sources would be eliminated. Second, in the absence of photosynthesis by plants and algae, there would be a reduction in oxygen levels in the atmosphere, affecting our ability to carry out key energy-related reactions in our cells
Why would a dark dust cloud that prevented sunlight from reaching Earths surface be potentially devastating to animal life?
A thick and dense dust cloud could prevent sunlight from reaching photosynthetic organisms at Earths surface. If these organisms are not able to “harvest” the energy ok sunlight, they will not be able to grow an store valuable molecules. This will seriously (and negatively) affect the ability of animals (including humans) to meet their nutritional and energetic needs
