A h e t e r o z y g o u s parent is crossed with a h o m o z y g o u s recessive parent. Complete a Punnett Square and answer the questions below.

All but one describes an effect of aging on the digestive system. a) decreased acid secretion b) decreased elasticity of stomach c) capacity to resist damage decreases d) food remains in stomach for less time

How are proteins and nucleic acids related? they both provide energy. they both carry genetic information. the structure of proteins is determined by nucleic acids. the subunits of nucleic acids are also the subunits of proteins.

This is a typical grassland food web. it is also a small picture of an important cycle on earth: the carbon cycle. describe how the carbon gets into this food web. a) bacteria and fungi, the decomposers, recycle carbon from dead organisms. b) carbon is found in the grass and is passed from one level to the next in this food web. eliminate c) all living things give off carbon dioxide as a by-product of respiration and it is released into the atmosphere. d) plants use carbon dioxide as a reactant in photosynthesis, to make usable chemical energy in the form of a sugar.