Describe the evolution of the vertebrate heart.
What will be an ideal response?
The structure of the heart in vertebrates shows an evolutionary sequence from two to four chambers. Amphibians have a three-chambered heart with two atria and a ventricle. Reptiles have a three-chambered heart with two atria and a ventricle that is incompletely divided into two partial chambers. Birds and mammals have four-chambered hearts with two atria and two ventricles. A four-chambered heart allows for separation of deoxygenated and oxygenated blood going to the capillaries of the lungs and all other capillaries, respectively. This increases the efficiency of the circulatory system, which is necessary adaptation for endothermic birds and mammals that have greater metabolic demand than the ectothermic amphibians and reptiles.
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Differentiation occurs only in multicellular organisms
Indicate whether the statement is true or false.
Saprobes do not need a carbon source for growth and metabolism.
Answer the following statement true (T) or false (F)
The level of genetic control that involves the processing of early RNA transcripts to mRNA and the rate at which mRNA leaves the nucleus is
A. feedback control. B. transcriptional control. C. translational control. D. posttranscriptional control. E. posttranslational control.
Which statement about chimpanzee behavior is true?
A) Only female chimpanzees are organized in a dominance hierarchy. B) Alpha males assert their status by making plant stems into tools for food extraction. C) Social primates do not show reconciliation-type behaviors. D) Grooming behavior is crucial to maintaining relationships within chimpanzee groups.