Answer:
New species can appear gradually through small changes in an ancestral species.
Explanation:
The new species that appear are due to hereditary variations that occur in a population. The adaptive variations are said to confer a selective advantage to organisms possessing them. The result of variations is that well adapted individuals are able to survive and reach the reproductive age and pass over their favourable characteristics to their offspring.
Answer:
Unisexual and bisexual organisms are differentiated based on the reproductive systems they posses. Unisexual organisms have separate sexes male or female. Male and female reproductive systems are present in different individuals hence unisexual organisms produce male or female gametes but never both. Bisexual organisms have both male and female reproductive systems within the same individual. Hence, they are capable of producing both types of gametes. Some flowers are unisexual, and they possess only pistils or stamens. Some flowers are bisexual, and they possess both stamens and pistils together. This is the difference between unisexual and bisexual organisms.
As food reaches the end of the esophagus, it enters the stomach through a muscular valve called the lower esophageal sphincter. The stomach secretes acid and enzymes that digest food. Ridges of muscle tissue called rugae line the stomach. The stomach muscles contract periodically, churning food to enhance digestion.Mar 4, 2016
Answer:
the bottom answer
Explanation:
carbohydrates are rapid energy.
