Anatomy And Physiology OA Final Actual Exam

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WGU D312 Objective Assessment /WGU D312 Anatomy And Physiology OA Final Actual Exam Newest 2026-2027 Actual Exam With Complete 250 Questions And Correct Detailed Answers (Verified Answers) |Already Graded A+

What is the primary function of the cell membrane in regulating the concentration of substances inside the cell? - ANSWER-The cell membrane regulates the concentration of ions, nutrients, and waste products inside the cell.

What is passive transport? - ANSWER-The movement of substances across the cell membrane without the expenditure of cellular energy.

What is active transport? - ANSWER-The movement of substances across the cell membrane using energy from adenosine triphosphate (ATP)

What is diffusion? - ANSWER-The movement of particles from an area of higher concentration to an area of lower concentration.

EX: The scent of perfume spreading in a closed room or sugar

dissolving in a cup of tea.

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How does temperature affect the rate of diffusion? - ANSWER-Higher temperatures increase the rate of diffusion as molecules move faster.

Why do oxygen (O2) and carbon dioxide (CO2) use passive transport to move across the cell membrane? - ANSWER-Because they can easily diffuse through the lipid bilayer due to their concentration gradients and do not require energy.

Why can't large polar or ionic molecules easily cross the phospholipid bilayer? - ANSWER-Because they are hydrophilic and are repelled by the nonpolar tails in the interior of the phospholipid bilayer.

What is facilitated diffusion? - ANSWER-The diffusion process used for substances that cannot cross the lipid bilayer due to their size, charge, and/or polarity.

How does glucose enter the cell if it cannot cross the lipid bilayer via simple diffusion? - ANSWER-Through a specialized carrier protein called the glucose transporter, which facilitates its inward diffusion.

What is osmosis? - ANSWER-The diffusion of water through a semipermeable membrane.

What happens to cells in a hypertonic solution? - ANSWER-Cells will shrivel as water leaves the cell via osmosis. 2 / 4

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Why is it important for cells to be in an isotonic environment? - ANSWER-To ensure the concentration of water molecules is the same outside and inside the cells, maintaining their normal shape and function.

What is the main difference between diffusion and filtration in passive transport? - ANSWER-Diffusion moves substances from an area of higher concentration to lower concentration, while filtration uses a hydrostatic pressure gradient to move fluid and solutes from a higher pressure area to a lower pressure area.

How does the circulatory system use filtration? - ANSWER-The circulatory system uses filtration to move plasma and substances across the endothelial lining of capillaries into surrounding tissues, supplying cells with nutrients.

What is the role of ATP in active transport? - ANSWER-ATP is required to move substances across a membrane, often with the help of protein carriers, and usually against their concentration gradient.

Describe the function of the sodium-potassium pump. - ANSWER-The sodium-potassium pump transports sodium out of the cell and potassium into the cell, maintaining an electrical gradient across the cell membrane. It moves three sodium ions out and two potassium ions in for each ATP molecule used. 3 / 4

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What are the tiny passageways that allow the passage of proteins, RNA, and solutes between the nucleus and the cytoplasm? - ANSWER- Nuclear pores

What is the region of the nucleus responsible for manufacturing the RNA necessary for the construction of ribosomes? - ANSWER- Nucleolus

What is a single, wrapped DNA-histone complex called? - ANSWER- Nucleosome

What is the condensed form of chromatin that is composed of DNA and proteins? - ANSWER-Chromosome

What is the term for the full complement of proteins in a cell? - ANSWER-Proteome

What is a functional segment of DNA that provides the genetic information necessary to build a protein? - ANSWER-Gene

What process transforms the information coded in a gene to a final gene product, ultimately dictating the structure and function of a cell? - ANSWER-Gene expression

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