Homeostasis and Transport

Study Questions

1.         What is homeostasis?

2.         Define negative feedback?

3.         What is a set point?

4.         What three things are required for negative feedback?

5.         What is the purpose of receptors?

6.         What causes an effector to take action?

7.         Describe an example of negative feedback?

8.         What drives passive transport?

9.         What is the direction of passive transport?

10.       What provides the energy for passive transport?

11.       What determines the rate of diffusion?

12.       When does diffusion stop?

13.       What determines the permeability of a cell membrane?

14.       What types of molecules are able to diffuse across the cell membrane?

15.       How does the lipid bilayer of a membrane form a barrier to molecules?

16.       What is facilitated diffusion?

17.       What is a carrier protein?

18.       Describe the action of carrier proteins in facilitated diffusion?

19.       Compare diffusion and facilitated diffusion.

20.       Why are ion channels necessary?

21.       Describe the function of ion channels?

22.       How many types of ions can pass through one ion channel?

23.       What causes an ion channel to open?

24.       What is osmosis?

25.       How is osmosis related to diffusion?

26.       Define hypotonic, hypertonic and isotonic.

27.       If the concentration of solute molecules outside a cell is lower than the cytosol, is to external environment hypotonic, hypertonic, or isotonic to the cytosol?

28.       What is turgor pressure?

29.       In terms of osmosis, what causes a plant to wilt?

30.       What type of transport can move materials from a low to a high concentration?

31.       What is necessary for active transport?

32.       What is the function of carrier proteins in active transport?

33.       Compare primary and secondary membrane pumps.

34.       Describe the action of the Na⁺-K⁺ pump.

35.       What provides the energy for the Na⁺-K⁺ pump?

36.       Describe the function of a symport.

37.       Compare endocytosis and exocytosis.

38.       What is the purpose of exocytosis?

39.       Explain the difference between active transport and passive transport.

40.       Explain the difference between pinocytosis and phagocytosis.

41.       How is ATP involved in active transport?