Exam 3 Biology Chapter 8 Cell Division

A polyploid individual has______

A complete extra set of chromosomes

What is the main prerequisite for clearance at the G2 checkpoint?

Accurate and complete DNA replication

Plants utilize a(n) _________ life strategy

Alteration of generations

During __________, homologous chromosomes are separated

Anaphase I

At which stage of meiosis are sister chromatids separated from each other?

Anaphase II

What is the difference between autosomes and sex chromosomes?

Autosomes are matched pairs, meaning there are two copies. Sex chromosomes are really just one pair which may or may not be matched.

A key event that occurs in meiosis is____________

Crossing over during meiosis I

What regulator molecules occur in positive regulation of cell cycle checkpoints?

Cyclins, cyclin-dependent kinases (Cdks)

Cell division is not complete until __________, the physical separation of the daughter cell, occurs.

Cytokinesis

Select the statements below that describe the chromosomes of the human body

Each body cell contains 2 sets of 23 chromosomes

Recombinant chromosomes contain________

Fragments of DNA exchanged between homologues

After the _________ checkpoint, a cell is irreversibly committed to dividing.

G1

During the ______ phase, the cell accumulates building blocks and energy resources to copy its genome

G1

The part of meiosis that is similar to mitosis is

Meiosis II

Even though the processes are very similar, mitosis and meiosis are two very distinct processes. What is the difference between meiosis and mitosis?

Mitosis results in two identical sister cells genetically identical to the original parent cell, while meiosis also starts with diploid but results in haploid cells

______ is the first stage of mitosis in which the nuclear envelop disassembles

Prophase

What are the functions of negative regulation molecules Rb, p53, and p23?

Rb- Tumor suppressor protein p53- halts cell cycle and recruits enzymes to repair DNA. Can trigger apoptosis p23- enforces halt of cell cycle facilitated by p53.

In order for cancer to develop, a ______ would need to be inactivated

Tumor suppressor gene

Fibrous proteins pack ______ once it is formed to ensure ______ do(es) not overlap in the nucleus during cell division

chromatin, chromosomes

Assume a pericentric inversion occurred in one of two homologues prior to meiosis. The other homologues remain normal. During meiosis, what structure-if any- would these homologues assume in order to pair accurately along their lengths?

loop

A nondisjunction event in _______ causes all gametes to be mutant

meiosis I

A _______ inversion is capable of changing the relative length of chromosome arms.

pericentric

The structure that gives rise to the cell plate in plant cells is called a __________

phragmoplast