Human Biology Chapter 20: Cancer

With a "gain-of-function" or dominant gene mutation, such as one that converts a proto-oncogene into an oncogene, how many copies of the gene must be mutated for the effect to occur?

- 1, one

In normal cells, the telomeres get shorter and shorter, and repair enzymes eventually cause the ends of chromosomes to ...

- Bind together

Cells from malignant tumors typically spread throughout the body by invading...

- Blood and lymphatic vessels.

The term for development of cancer is...

- Carcinogenesis

Arrange these phases in the development of cancer according to the order in which they typically occur, with the earliest event at the top.

1. A single cell undergoes gene mutation(s) 2. Tumor formation leads to more mutations 3. Cancer in situ has formed 4. Tumor cells invade neighboring tissues

Proto-oncogenes -> Tumor suppressor genes ->

Proto-oncogenes -> codes for proteins that promote the cell cycle and prevent apoptosis. Tumor suppressor genes -> codes for proteins that inhibit the cell cycle and promote apoptosis.

The gain of which function would most directly allow a tumor cell to invade underlying tissues?

- Cancer cells produce proteinase enzymes that degrade the basement membrane and allowing them to invade.

Human body system with the type(s) of cancer that can arise there: Cardiovascular system -> Digestive system -> Endocrine system -> Integumentary system -> Lymphatic system -> Reproductive system -> Respiratory system ->

- Cardiovascular system -> leukemia and plasma cell tumors. - Digestive system -> colorectal (colon/rectum) cancer those of the pancreas, stomach, esophagus, and other organs. - Endocrine system -> Thyroid cancer - Integumentary system -> melanoma, squamous cell carcinoma. - Lymphatic system -> Hodgkin (developed from mutated B cells) or non-Hodgkin lymphoma (can arise from B cells or T cells). - Reproductive system -> breast cancer and prostate cancer. - Respiratory system -> lung caner

Contact inhibition occurs when cells...

- Come in contact with other cells and they stop dividing.

Cancer cells do not resemble specialized cells in the body that have specific structures and functions. In other words, cancer cells lack cellular...

- Differentiation

Cyclins are proteins that...

- Direct the cell through the cell cycle.

True or false: Cancer cells undergo apoptosis as regularly as normal cells.

- False

True or false: Tumors consist of cells in a single layer that exhibit contact inhibition.

- False, because tumors grow in multiple, disorganized layers.

Angiogenesis is defined as...

- Formation of new blood vessels.

Cancer cells can usually grow even in the absence of cell division-stimulating proteins called...

- Growth factors

Carcinogenesis with the correct description: Initiation -> Promotion -> Progression ->

- Initiation -> a single cell undergoes a mutation that leads to uncontrolled cell division. - Promotion -> a tumor develops and continue to undergo mutations. - Progression -> cells become invasive and can spread.

Which of the following are characteristics of cancer cells?

- Lacks differentiation - Undergo metastasis - Stimulate angiogenesis

Which of the following contain tissue types with cells that divide frequently and as a result might be more prone to cancer?

- Lining of digestive tract and lining of respiratory tract.

When tumor suppressor genes mutate, their products no longer inhibit the cell cycle nor promote apoptosis. Therefore, these mutations can be called...

- Loss-of-function mutations

What type of tumors have abnormal cells and are able to invade surrounding tissues?

- Malignant

In general, Ras proteins promote...

- Mitosis

A low grade fever, blood in urine and decrease in appetite are potential symptoms of...

- Nephroblastoma

What genes code for proteins that promote cell division and the cell cycle?

- Proto-oncogenes

Types of cancers that may affect men.

- Testicular cancer - Prostate cancer - Breast cancer

All common cellular abnormalities exhibited by cancer cells...

- The nuclei of cancer cells are enlarged but not the cells themselves. - Abnormal number of chromosomes - Gene amplification - Defective chromosomes - Deletion - Duplication

The most common cancer of the human endocrine system is...

- Thyroid cancer

The major defining feature of cancer is ...

- Uncontrolled cell growth

Another term for programmed cell death is _______.

- apoptosis

Some tumors are classified as _____ because their cells resemble normal cells and they are surrounded by a capsule of connective tissue.

- benign

A growth factor is a chemical signal that activates a cell-signaling pathway, resulting in...

- cell division

Cancers of the blood are called _______.

- leukemias

The spread of cancer from its place of origin to elsewhere in the body is called _____.

- metastasis

A medical specialist in cancer is called a(n)?

- oncologist

The _________ can turn on genes that can stop the cell cycle via apoptosis.

- p53 protein

When an oncologist discusses a patient's prognosis, he/she is referring to the...

- probable outcome

The ends of chromosomes have repetitive DNA sequences called _____.

- telomeres

Since cancer cells do not exhibit contact inhibition, they pile on top of each other forming a _____.

- tumor