The osmotic gradient in the medullary region of the kidneys is established and maintained by which of the following?

A. Horizontes: O Centro e o Norte de Portugal: In Lição 8 you learned a little bit about the Center and the North of Portugal in Horizontes. Can you recall some of the main points? First, read each statement below. Then, indicate whether each statement is true or false by selecting Certo (true) or Falso (false). Select your answer from the dropdown menu. (1 pt. each; 7 pts. total)   1. Coimbra é famosa pela universidade, uma das mais antigas da Europa. [blank1] 2. A Ponte Maria Pia no Porto foi construída pela empresa de Gustave Eiffel. [blank2]  3. O Parque Nacional da Serra da Estrela é um destino turístico pouco famoso. [blank3] 4. O ponto mais alto de Portugal está na Serra da Estrela. [blank4]  5. A cidade do Porto não está no Norte de Portugal. [blank5] 6. A Casa da Música no Porto é muito antiga e foi inaugurada em 1870. [blank6]  7. O vinho do Porto é muito conhecido internacionalmente. [blank7]

Container A holds 762 mL of an ideal gas at 2.40 atm. Container B holds 144 mL of a different ideal gas at 4.90 atm. if the gases are allowed to mix together, what is the resulting total pressure?

Flat, erosional surfaces left after continental glaciers move over an area are called:

There are four driving factors in dune formation. Which of the following does not contribute to dune shape?

Running water causes most erosion in deserts.

Long ridges of sand aligned parallel to wind direction are __________ dunes.

Today, deserts make up only 10% of Earth’s land surface.

The zone of accumulation and zone of wastage are separated by the:

A nurse is reviewing the function of the renin–angiotensin–aldosterone system (RAAS) with a group of students. Which statement by a student indicates an understanding of how the RAAS helps regulate blood pressure?