UNIT 2: Concept 2 Cell Transport STUDY GUIDE
Describe (either with words or drawings) the six types of transport. List examples of substances transported via each method.
Simple Diffusion-Random movement of a substance from a region of higher concentration to lower concentration Facilitated Diffusion-Random movement of a substance from a region of higher concentration to lower concentration Osmosis-Water moves across the membrane from a region of higher water concentration to a region of lower water concentration Active Transport-Substances move across membrane with the aid of a carrier protein and energy supplied by the cell Endocytosis-A region of the plasma membrane engulfs the substance to be ingested and then pinches off from from the rest of the membrane so it is enclosed in a vesicle Exocytosis-Opposite of endocytosis
Classify a type of cell transport as active or passive based on a diagram or description.
Spreading of molecules across a membrane until they are equally concentrated on both sides of the membrane.-passive
Describe the relationship between a response to stimuli and homeostasis.
Both external and internal stimuli can cause a response from an organism. Organisms respond to external stimuli to maintain homeostasis.
vocabulary
Homeostasis-the need of an organism to maintain and regulate constant/stable internal conditions Solute-the minor component in a solution, dissolved in the solvent Solvent-able to dissolve other substances Solution-a liquid mixture in which the minor component (the solute) is uniformly distributed within the major component (the solvent) Concentration-the amount of solute per unit volume of solution
Differentiate between dynamic and static equilibrium with regards to homeostasis.
Dynamic equilibrium is the steady state of a reversible reaction where the rate of the forward reaction is the same as the reaction rate in the backward direction. Static equilibrium, also known as mechanical equilibrium, means the reaction has stopped. In other words, the system is at rest.
Differentiate between passive and active transport.
Active transport moves molecules and ions from lower concentration to higher concentration with the help of energy in the form of ATP. On the other hand, passive transport moves molecules and ions from a higher concentration to lower concentration without any energy
Explain the role of the cell membrane in maintaining homeostasis on a cellular level.
One way that a cell maintains homeostasis is by controlling the movement of substances across the cell membrane.
Infer which type of cell transport would be best suited to move a given substance across the cell membrane based on a diagram or description.
Passive transport or facilitated diffusion.
Differentiate between positive and negative feedback loops. Include two examples of each.
Positive feedback loops enhance or amplify changes; this tends to move a system away from its equilibrium state and make it more unstable. Negative feedbacks tend to dampen or buffer changes. Some examples of positive feedback are contractions in childbirth and the ripening of fruit; negative feedback examples include the regulation of blood glucose levels and osmoregulation.
