Final Flashcards
(779 cards)
The process of photosynthesis results in the formation of two substances essential to our existence:
sugar and oxygen.
Life existed on Earth as early as ______ years ago.
3 to 4 billion
Which of the following statements about stromatolites is FALSE?
They are fossil structures, with none alive today.
On Mars, there is evidence for the presence of water in the form of______.
ice, liquid water and snow
Which of the following statements about proteinoid microspheres is FALSE?
They are thought to be the first forms of life.
Which of the following statements concerning primitive cells is FALSE?
They constructed new cells from organic molecules made via photosynthesis.
A heterotroph:
is exemplified by a fungus.
Which of the following statements about photosynthetic autotrophs is FALSE?
They obtain their required organic compounds from external sources.
Which of the following statements concerning the earliest photosynthetic organisms is FALSE?
They have been found in rocks 4 billion years old.
The oxygen gas released in photosynthesis originates from:
water.
Atmospheric levels of oxygen gas approached modern levels approximately ______ years ago.
500 million
Ozone in the outer layer of the atmosphere has important consequences for living things in that it:
absorbs ultraviolet rays from sunlight.
Respiration refers to the process by which organisms:
break down molecules under aerobic conditions.
Prokaryotic cells differ from eukaryotic cells in that prokaryotic cells:
lack a nuclear envelope.
Which are prokaryotic organisms?
cyanobacteria and archaea
The first cells on Earth were most likely:
archaeans.
Which of the following is NOT an adaptation of photosynthetic organisms to rocky coasts?
pigment systems
The function of the cuticle is:
retarding water loss.
The function of stomata is:
regulating the exchange of gases.
Which of the following statements concerning stomata is FALSE?.
They form a waxy covering on all aboveground portions of the plant.
In perennials, the ______ is most similar in function to the cuticle-covered epidermis of annuals.
cork
Water is transported upward through the plant body in the:
xylem.
The food manufactured by photosynthesis is transported throughout the plant body in the:
phloem.
The function of phloem is to ______.
transport food