Evolution :).
Descent with modification helps to explain anatomical similarities among certain species. The bones of the forelimbs of humans, cats, and bats (you can add in penguins, alligators, and more) are used in different ways but have similar structures.
The best explanation is that these animals have a common ancestor. With new generations, new species emerged by natural selection from different populations, and with this, the bones become better for different tasks.
The forelimbs and other such structures with anatomical similarities due to a common ancestor are called homologous structures.
Answer: The statement is false
Explanation:
A community refers to a group of plants and animals that occupy a given area and can adapt to the conditions of their environment. Hence, community include biotic factors (living organisms) and abiotic factors (non-living factors like soil, weather etc).
Thus, the statement is false
The condition which is most likely to cause death of a botulism patient is Respiratory failure.
Explanation:
The causal organism of Botulism is the bacteria <em>Clostridium botulinum.</em>
It is usually found in canned food and causes a very severe food poisoning.
The bacteria release botulinum toxin on reaching the intestine of the person and from their the toxins are absorbed into the blood.
Botulism mainly effects the neuromuscular system of the body. .
The basic symptoms of botulism is characterised by weaknes in limbs , jaws and eyes.
A decreased muscular activity sometimes causes constipation due to slowed down peristalsis.
Sometimes nausea , vomiting and diarrhea may occur.
If left untreated and in severe cases, the toxins may proceed to effect the respiratory muscle thus hindering the proper breathing and gaseous exchange.
A further damage could result in the respiratory failure.
Answer:
Dust bowl resulted from extreme drying and loosening of the soil that resulted in soil erosion by wind. Thus, it can be related that poor agricultural practices like over plowing , over grazing and leaving the land barren are human activities that must have contributed to the dust bowl.
Explanation:
- Dust bowl is referred to a period in early twentieth century when the the American and Canadian prairies faced severe dust storms.
- These dust storms resulted from severe drought and failure of practices to prevent soil erosion.
- Several people and livestock died as a result of choking.
- Over plowing, removal of top soil and small grasses exposed the soil to eroding winds and caused the dust storms.
