Cell Cycle and Cancer Genetics Review

A set of flashcards to help review key concepts related to the cell cycle, cancer, and genetics, capturing important processes and definitions.

What is the term for programmed cell death?

Apoptosis

Cancer is best described as:

Unregulated cell division.

Duplicated chromosomes are also known as sister:

Chromatids.

Mutations in DNA are BEST described as an error in:

DNA.

Why aren't all mutations that occur in DNA inherited by offspring?

Only mutations in the DNA contained in the sperm and eggs will be inherited.

At the G1 checkpoint, cells pause to:

Wait until a need arises for them to divide.

The G2 checkpoint checks whether the:

DNA has been replicated properly.

At the end of interphase, each chromosome is made up of:

Sister chromatids.

A proto-oncogene is a gene that:

Tells the cell to go through the cell cycle.

The process of _ is used to replace damaged or worn-out cells.

Mitosis.

Which of these occurs during interphase?

Replication of chromosomes.

What would be a likely result if a cell divides before properly completing mitosis?

Two cells with either extra or missing chromosomes.

A cell divides before properly completing S phase. What is a likely result?

Two cells with some missing DNA.

Colchicine interferes with microtubule formation. Which stage of the cell cycle would it affect?

Mitosis.

Chromosomes line up in the middle of the nucleus during:

Metaphase.

At the end of the S phase, cells have _ set(s) of genetic material compared to a cell at the beginning of S phase.

2.

During mitosis, sister chromatids are:

Held together by the centromere.

DNA damage is usually repaired:

At or before checkpoints in the cell cycle.

By what stage in mitosis are sister chromatids completely separated into what will become two new daughter nuclei?

Anaphase.

Chromosomes first coil up and become visible during:

Prophase.

A newly divided cell grows to mature size during:

G1.

Which type of mutation is LEAST likely to lead to cancer?

A mutation in a noncoding sequence of a gene.

What is the number-one preventable cause of cancer?

Smoking.

What happens if a proto-oncogene is mutated?

The cell cycle would continue without stopping when needed.

A gene found in a somatic cell is mutated. What is a likely result?

Cancer.

Proteins scan chromosomes for damage during the:

G1 checkpoint.

Cell division is usually kept under control by:

Several checkpoints in the cell cycle and by apoptosis.

In _, chromosomes align in the middle of the cell, tugged there by spindle fibers.

Metaphase.

Chromosomes are MOST stretched out during:

Interphase.

The correct order of phases in mitosis is:

Prophase, metaphase, anaphase, and telophase.

Chromosomes are duplicated during:

The S phase.

After chromosomes are duplicated, the identical copies:

Are attached to each other by a centromere.

Radiation therapy for cancer works by:

Damaging the cell's DNA, resulting in cell death.

BRCA1 and BRCA2 are , p53 is a , and Her2 is a _.

Tumor suppressor genes; tumor suppressor gene; proto-oncogene.

Why does inheriting a mutation in a gene increase one's risk of developing cancer?

It takes more than one mutation to develop cancer. A person who inherits a mutation needs fewer additional mutations.

What kind of mutation causes MOST types of cancer?

Mutations in cell cycle genes.

How could a cancerous cell evade apoptosis?

The cell has a mutation in a checkpoint protein.

In addition to breast cancer, women with a mutation in one of their BRCA genes have an increased likelihood of developing which other type of cancer?

Ovarian.

A healthy cell spends MOST of its lifetime in:

Interphase.

Why does cancer affect older individuals more frequently than younger people?

Older people have had more time to accumulate mutations.

Sister chromatids are separated from each other during:

Mitosis.

A tumor suppressor gene is a gene that:

Tells the cell when to stop the cell cycle.

Mutations that cause the cell to divide rapidly, even in the absence of a signal to divide, are usually mutations of:

Proto-oncogenes.

Which series of steps would MOST likely lead to tumor formation?

A mutated tumor suppressor gene is inherited, other mutations in proto-oncogenes occur, and the cell rapidly divides and spreads.

How many different versions (alleles) of a gene can an individual have?

Only two: one from the individual’s father and one from the mother.

Which of these would MOST likely increase an individual's risk of cancer?

A mutation in a gene for a DNA-repairing enzyme.

Cancer consists of too much:

Cell division.

Permanent activation or overexpression of proto-oncogenes:

Has been linked to breast cancer.

Which cell type goes through the cell cycle MOST frequently?

Skin cell.

In healthy cells, if a mutation occurs in a proto-oncogene, what is the gene now termed?

Oncogene.

In normal cells, tumor suppressors are:

Required for DNA repair or programmed cell death.

Cell division in cancerous tumors:

Accumulates DNA damage.

Most chemotherapy drugs are effective because they:

Interrupt cell division.

Why do people with inheritable high-risk mutations develop cancer at an earlier age?

They require fewer additional mutations.

What causes cancer to kill people?

Cancer cells crowd out normal cells and disrupt organ functions.

A cell has 46 centromeres in G1. How many will be present in anaphase?

46.

What would happen if a proto-oncogene, such as Her2, were mutated?

The cell cycle would continue without stopping when needed.

The nuclear envelope reforms during:

Telophase.

If a cell is irreparably damaged, it undergoes programmed cell death, called:

Apoptosis.

Metastasis is:

The spread of cancer from one location in the body to another.

The end result of mitosis and cytokinesis is:

Two cells identical in genetic material.

Cytokinesis occurs in animal cells when:

The cell membrane pinches to form two separate cells.

Side effects of chemotherapy, such as vomiting and hair loss, occur because:

Chemotherapeutic drugs kill both normal and cancerous cells.

What types of genes tell a skin cell to move on past the G1 checkpoint?

Proto-oncogenes.

A normal BRCA1 allele produces normal protein that:

Allows cells to repair DNA damage.

Organelles duplicate during:

G2 phase.

Proto-oncogenes are:

Required for normal cell division.

The nuclear envelope breaks up, allowing spindle fibers to attach to chromosomes during:

Prophase.

When cancer has spread to many areas of the body, the MOST common form of treatment is:

Chemotherapy drugs injected into the bloodstream.

Choose the sequence that gives the MOST correct and complete order of events during the cell cycle.

G1, S, G2, mitosis, and cytokinesis.

Chemotherapeutics act on:

All dividing cells.

At what stage of mitosis do the spindle fibers shorten, thereby pulling apart sister chromatids?

Anaphase.

A new gene, called GRAB, prevents a cell from entering mitosis if there are any signs of DNA damage. GRAB would be a type of:

Tumor suppressor gene.

The enzyme that copies DNA makes errors, but the actual error rate in newly copied DNA is lower. How is that possible?

There are other enzymes that find errors in DNA and repair them.

The amount of DNA in a cell doubles during:

S phase.

Which of these would NOT lead to cancer?

A mutated proto-oncogene.

Which phase(s) occur(s) during interphase?

G1, S, and G2.

Which stage of the cell cycle is the lengthiest?

Interphase.

When chromosomes duplicate, they form:

Sister chromatids.

Sister chromatids begin separation during which phase of the cell cycle?

Anaphase.

Where is the CFTR protein found?

In cells lining the lungs.

Humans have 23 pairs of chromosomes. How many possible ways can they be sorted out during independent assortment?

More than 8 million ways.

If protein X is not folded properly, what might happen to the cell?

The cell would have an impaired ability to generate energy.

In a cross between an individual who is heterozygous for Huntington disease and an unaffected individual, what are the chances their progeny will have the disease?

50%.

Two normal individuals have a child who has cystic fibrosis. What were the chances of this happening?

1:4 chance.

Which statement is true of crossing over?

Crossing over results in unique combinations of alleles.

Cystic fibrosis is the result of a nonfunctional protein that regulates:

Sodium and chloride transfer across cell membranes.

The appearance of an organism is known as its:

Phenotype.

The deletion of a codon in the gene for CF causes the CFTR protein to:

Become nonfunctional.

How many chromosomes are in a gamete?

23.

How are the X and Y chromosomes in males different from other chromosomes in diploid cells?

Genes on the X and Y chromosomes do not have a second copy.

A human female has how many pairs of homologous chromosomes?

23.

Which represents a cross between two individuals who are heterozygous for a single trait?

Aa → Aa.

A mutation in DNA can:

Lead to all of these.

If a trait is not displayed in the phenotype, it is called:

Recessive.

Two normal individuals have a child who has cystic fibrosis. What were the chances of this happening?

1:4 chance.

What are homologous chromosomes?

Paired chromosomes that are inherited from either the mother or the father.

How is the sequence of amino acids in a protein determined?

By codons in the DNA, which are read in 3-base increments.

Alleles are located:

At a specific position on each of a pair of chromosomes.

An allele is defined as:

An alternate version of a gene.