During telophase, the cell looks like it’s reversing the dramatic changes of earlier mitosis. Two clusters of chromosomes sit at opposite ends of the cell, each gradually losing their distinct, rod-like shape as they unwind into thinner, harder-to-see threads. A new nuclear membrane forms around each cluster, and the spindle fibers that pulled the chromosomes apart are mostly gone. If cytokinesis has started, you may also see the cell pinching inward at its center.
Chromosomes Losing Their Shape
The most recognizable visual change during telophase is what happens to the chromosomes. Throughout earlier stages of mitosis, chromosomes are tightly coiled and easy to spot under a microscope as dark, compact structures. In telophase, they begin to uncoil and spread out, a process called decondensation. Under phase-contrast microscopy, this gives the forming nuclei a noticeably brighter, more diffuse appearance compared to the dark, crisp chromosome clusters visible just moments earlier in anaphase.
By the end of telophase, individual chromosomes are no longer distinguishable. They’ve relaxed back into the loosely spread form of chromatin that fills the nucleus during the cell’s normal working state. This is the same form they were in before mitosis began.
Nuclear Envelopes Rebuilding
While chromosomes are unwinding, a new nuclear membrane is assembling around each set. This doesn’t happen all at once. Small membrane fragments (vesicles left over from when the original nucleus broke apart) first attach to the surface of the chromosomes. These vesicles initially wrap around individual chromosomes, then fuse with each other to form a continuous double membrane enclosing the entire group.
The process follows a specific order. The inner membrane layer attaches to chromosomes first, starting as early as late anaphase. Then nuclear pores, the tiny channels that control what enters and exits the nucleus, reassemble within the membrane. A structural scaffold called the nuclear lamina reforms on the inner surface, providing shape and support. One key structural protein begins concentrating on the chromosome surfaces right as they reach the poles of the cell, while another only joins after the pores and membrane are already in place. The result is two fully enclosed, functional nuclei.
As the envelopes close, they immediately start excluding molecules from the surrounding cytoplasm. The nucleolus, the small dense body inside the nucleus responsible for building components of the cell’s protein-making machinery, also reappears and enlarges. By the end of telophase, both daughter nuclei have grown to their normal working size.
Spindle Fibers Disappearing
The spindle, that football-shaped network of fibers stretching across the cell during metaphase and anaphase, is largely dismantled by telophase. The fibers that were attached to chromosomes (kinetochore microtubules) have been shortening throughout anaphase, losing material from both ends simultaneously. By telophase, they’ve nearly vanished. As the chromosomes arrive at the poles, they release from whatever spindle fibers remain.
Some overlap fibers in the middle of the cell do persist, though. These play a role in continuing to push the two halves of the cell apart, and they help guide the physical division of the cell that’s already underway.
The Cell Begins to Split
Telophase overlaps significantly with cytokinesis, the physical division of the cell into two. Cytokinesis actually starts during anaphase and finishes as telophase ends and the new cells enter their resting state. So when you’re looking at a cell in telophase, you’re often seeing division happening at the same time.
In animal cells, this looks like a cleavage furrow: the cell membrane pinches inward around the middle, driven by a ring of contractile proteins that tightens like a drawstring. The furrow deepens throughout telophase until the cell is split in two. In plant cells, the process looks completely different. Because plant cells have rigid walls, they can’t pinch inward. Instead, a structure called the cell plate forms in the center and grows outward. Small vesicles from the cell’s internal transport system gather at the midline beginning in late anaphase, guided by the remaining spindle fibers, and fuse together to build a new wall between the two daughter cells.
Telophase in Meiosis
Meiosis has two rounds of division, which means there are two telophases, and they look different from each other and from mitotic telophase.
In telophase I, the cell divides into two daughter cells that each contain half the original chromosome number. Importantly, each chromosome in these cells still consists of two joined copies (sister chromatids), so the chromosomes can appear slightly thicker or more substantial than what you’d see after mitosis. The two resulting cells are also not genetically identical to each other, because chromosomes exchanged segments during an earlier stage. In some organisms, the nuclear envelope may only partially reform or may not reform at all before the second division begins.
Telophase II looks more like mitotic telophase. The sister chromatids have now separated, so each of the four final cells has a single copy of each chromosome. Nuclear envelopes reform fully, chromosomes decondense, and the cells complete their division. The end result is four cells, each with half the chromosome count of the original.
Identifying Telophase Under a Microscope
If you’re trying to pick out telophase on a slide, look for these features together: two distinct groups of chromosomes at opposite poles of the cell, chromosomes that appear fuzzy or less defined than the sharp structures visible in metaphase or anaphase, visible nuclear membranes forming around each group, and a cell that looks like it’s narrowing or dividing in the middle. The spindle should be mostly invisible.
The easiest way to distinguish telophase from late anaphase is the nuclear envelope. In anaphase, chromosomes are moving but still exposed to the cytoplasm with no membrane around them. In telophase, you can often see the beginnings of a boundary forming around each chromosome cluster. The chromosomes also look less distinct in telophase because they’re actively unwinding, whereas in anaphase they remain tightly condensed and sharply defined.