Answer:
The options are
A) they may affect several populations in an ecosystem
B) they cannot be caused by human activity
C) they affect food chains but not food webs
D) They have no effect on living organisms in an ecosystem him
The answer is A) they may affect several populations in an ecosystem
Explanation:
Environmental changes include deforestation and climate changes. Organisms depend on their habitat and climatic conditions for their survival because it determines their food availability too.
When environmental change occurs they may affect several populations in an ecosystem.
volume change it travels through all types the media......
Answer:
Analogous structures
Explanation:
These structures are similar but not derived from the common ancestor like homologous structures. Analogous structures are formed as a result of convergent evolution-type of evolution in which organisms develop on similar way but independently. An example of analogous structures are wings. Birds, insects and bats all have wings, with the same purpose (flight) but they evolved in their own way.
<span>Damming a river has a variety of effects on the freshwater ecosystem, more than just altering the flow from A to B. Dams create calm bodies of water, changing overall temperature regimes and sediment transport, leading to conditions which tend to favour generalist species. Loss of specialist species, particularly endemics, changes the community structure and leads to biotic homogenization. A dam will withhold sediment in the reservoir, not just decreasing the amount of substrate available to local freshwater species, but even impacting diadromous, estuarine and marine species much further downstream. The competition between resident species for food and breeding sites will increase as damming isolates populations, and perhaps more importantly, damming completely restricts migratory fish species. Isolation may lead to decreases in genetic diversity and therefore puts species at greater risk from disease. All of these effects may be exacerbated by changes in the surrounding land use. Overall, damming river flow will lead to both a loss of native species, but also an increase in exotic species which are more likely to become established in degraded habitats. For this reason, dams are one of the greatest global threats to freshwater biodiversity.</span>
They need approximately 70 grams of protein in their diet
