A laboratory homogenizer tube assembly that mounts to a homogenizer for homogenizing a sample by axially-reciprocal shaking, the laboratory homogenizer tube assembly comprising: two shell components that removably couple together to form an internal tube chamber with a longitudinal axis, a flow disrupter including a flow-interrupting body that extends generally transversely to the tube-chamber axis and into the tube chamber to divide the tube chamber into two axially-aligned fixed-volume sub-chambers when the tube chamber is sealed for axially-reciprocal shaking use, the body including at least two flow-interrupting impact surfaces and at least one flow-constricting passageway, wherein the at least one flow-constricting passageway is defined at least in part by and extends between the two flow-interrupting impact surfaces, has a cross-sectional flow area that is less than a cross-sectional flow area of the two sub-chambers, and forms a path for the sample to flow generally axially between the two sub-chambers in an accelerating then decelerating sequence in response to the axially-reciprocal shaking of the tube assembly, and wherein the at least two flow-interrupting impact surfaces are generally oppositely arranged on the flow-interrupting body facing in generally opposite axial directions, and wherein the two shell components cooperate with the two flow-interrupting impact surfaces to define the two sub-chambers, so that a first one of the impact surfaces is impacted by the sample as the sample flows in a first axial direction in a first one of the sub-chambers toward a second one of the sub-chambers, and a second one of the impact surfaces is impacted by the sample as the sample flows in a second axial direction in the second sub-chamber back toward the first sub-chamber during the axially-reciprocal shaking of the tube assembly. two shell components that removably couple together to form an internal tube chamber with a longitudinal axis, a flow disrupter including a flow-interrupting body that extends generally transversely to the tube-chamber axis and into the tube chamber to divide the tube chamber into two axially-aligned fixed-volume sub-chambers when the tube chamber is sealed for axially-reciprocal shaking use, the body including at least two flow-interrupting impact surfaces and at least one flow-constricting passageway, wherein the at least one flow-constricting passageway is defined at least in part by and extends between the two flow-interrupting impact surfaces, has a cross-sectional flow area that is less than a cross-sectional flow area of the two sub-chambers, and forms a path for the sample to flow generally axially between the two sub-chambers in an accelerating then decelerating sequence in response to the axially-reciprocal shaking of the tube assembly, and wherein the at least two flow-interrupting impact surfaces are generally oppositely arranged on the flow-interrupting body facing in generally opposite axial directions, and wherein the two shell components cooperate with the two flow-interrupting impact surfaces to define the two sub-chambers, so that a first one of the impact surfaces is impacted by the sample as the sample flows in a first axial direction in a first one of the sub-chambers toward a second one of the sub-chambers, and a second one of the impact surfaces is impacted by the sample as the sample flows in a second axial direction in the second sub-chamber back toward the first sub-chamber during the axially-reciprocal shaking of the tube assembly.