Imagine looking through a microscope at a squashed onion root tip. The chromosomes of many of the cells are plainly visible.  In some cells, replicated chromosomes are aligned along the center (equator) of the cell.  These particular cells are in which stage of mitosis?

For the following questions, match the key event of meiosis with the stages listed below. I. Prophase I V. Prophase II II. Metaphase I VI. Metaphase II III. Anaphase I VII. Anaphase II IV. Telophase I VIII. Telophase II Tetrads of chromosomes are formed; crossing over at the chiasmata occurs between sister chromatids.

A patient has had a serious accident and lost a lot of blood.  In an attempt to replenish body fluids, distilled water, equal to the volume of blood lost, is transferred directly into one of his veins.  What will be the most probable result of this transfusion?

Red-green color blindness is a sex-linked recessive trait in humans.  Two people with normal color vision have a color-blind son. What are the genotypes of the parents?

Synapsis of homologous chromosomes and crossing over occurs during

Which of the following sequences correctly represents the flow of electrons through the linear (noncyclic) electron flow of the light reactions of photosynthesis:

If there are 60 chromatids in a cell at metaphase, how many chromosomes are there in each daughter cell following cytokinesis?

You have isolated DNA from three different cell types of an organism, determined the relative DNA content for each type, and plotted the results on the graph shown in Figure 13.3. Refer to the graph to answer the followingquestions.Figure 13.3Which sample might represent a sperm cell?

For the following questions, match the key event of meiosis with the stages listed below. I. Prophase V. Prophase II II. Metaphase I VI. Metaphase II III. Anaphase I VII. Anaphase II IV. Telophase I VIII. Telophase II Tetrads of chromosomes are aligned at the equator of the spindle; alignment determines independent assortment.

Plasmodesmata are small channels that directly connect the cytoplasm of neighboring plant cells to each other, establishing living bridges between cells. Question: In comparing eukaryotic animal and plants, which structures are most like these particular small channels?