Cellular Transport and Homeostasis

Which cell function is MOST directly dependent on the cytoskeleton?

• transport of material inside the cell

• response of the cell to external pathogens

• storage of energy in stable long-term forms

• direction of cellular activity

Which of these would be a model of diffusion?

• a student passes through a revolving door

• two students pass by each other in a hallway

• two students bump into each other in a crowded subway car

• many students pass from a crowded room into an empty hallway

Which two protein molecules are essential for muscle contraction and relaxation?

• actin and myosin

• collagen and tubulin

• hemoglobin and myoglobin

• amylase and polymerase

Which of these will occur if myosin fails to bind to actin during muscle contraction?

• The muscle cells will lose ATP.

• The muscle cells will remain relaxed.

• The muscle cells will produce lactic acid

• The muscle cells will lose calcium ions.

Newly made proteins are modified in which organelle?

• ribosome

• endoplasmic reticulum

• mitochondrion

• nuclear envelope

Which component of the cell membrane functions to actively transport molecules into the cell?

• carbohydrate

• cytoplasm

• phospholipid

• protein

Which process moves an ion across a cell membrane against the concentration gradient?

• diffusion

• exocytosis

• facilitated diffusion

• active transport

Which of the following travels from neuron to neuron as information is transmitted?

• electrochemical impulses

• RNA strands

• transport vesicles high in ATP

• mechanical forces

Electron transport in mitochondria results in a chemiosmotic gradient of which particle across the mitochondrial membrane?

• ADP

• ATP

• protons

• neutrons

Which cellular structure in an animal cell helps maintain homeostasis by controlling the transportation of substances into and out of the cell?

• vacuole

• cell wall

• mitochondrion

• cell membrane