Various types of Australian marsupials have often been compared with similar types of placentals (e.g., gliding squirrels and gliding possums) as examples of convergent evolution

However, there is no equivalent among marsupials to a placental whale or even to a seal. What is a possible reason for this?


As marsupial young complete their development in the pouch, prolonged submergence would cause them to drown. Additionally, giving birth underwater (like a whale) would be impossible because the tiny neonate would be swept away.

Anatomy & Physiology

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The kidneys are the first line of defense against changes in acid-base balance because they are the most powerful mechanism for maintaining pH

Indicate whether the statement is true or false

Anatomy & Physiology

If you have three threads laying on top of each other on a slide and you are focused on the top-most thread, then ________

A) all three threads should be in clear focus B) you are ready to rotate the ocular lens C) neither the middle nor the bottom-most thread will be in clear focus D) the middle thread will also be in clear focus

Anatomy & Physiology

____________________ are molecules produced by nerve cells and bind to nonsynaptic receptors

Fill in the blank(s) with correct word

Anatomy & Physiology

Hypovolemia refers to a reduction in total body water while maintaining normal osmolarity.

Answer the following statement true (T) or false (F)

Anatomy & Physiology