An organ or group of specialized cells in the body that produces and secretes a specific substance, such as a hormone
<span> Some of the important features of a prokaryotic cell is that it contains a plasma membrane, ribosomes, and genetic material (DNA) that is not bound by a membrane. Therefore, prokaryotic cells lack a nuclear membrane. </span>
Answer:
A food chain is a representation of what eats what in an ecosystem.
A combination of food chains is termed as a food web.
Example of two food chains in a food web are :
Example No 1:
Plant----- Grasshopper------ Frog---snake--- bacteria
Example No 2:
Plant---- rabbits---- fox---- bacteria
In a food chain, producers are usually plants and algae which are able to make their own food. Consumers feed on the plants. In example no 1, grasshoppers are primary consumers, frogs are secondary consumers, snakes are tertiary consumers.
In example no 2,plants are producers, rabbits are primary consumers and foxed are secondary consumers.
Decomposers are organisms that feed on the dead organisms in a food chain. In both the examples of food chain, bacteria are the decomposers.
Crossing over at prophase I results in the linked genes (those on the same chromosome) becoming unlinked and separated. Prophase I is this first stage of meiosis, the chromosomes condense, form tetrads, and exchange DNA. The nucleolus and nuclear envelope disappear.