Cancer Unit study guide

asexual reproduction

process of reproduction involving a single parent that results in offspring that are genetically identical to the parent

sexual reproduction

A reproductive process that involves two parents that combine their genetic material to produce a new organism, which differs from both parents

purpose of asexual reproduction

propagate ones own genes
Helps produce large amounts of offspring in short amount of time

Mitosis

cell division in which the nucleus divides into nuclei containing the same number of chromosomes
Happens in all eukaryotes

binary fission

A form of asexual reproduction in single

Vegetable propagation

Asexual reproduction carried out by plants where the root, stem or leaf produces a genetic copy of the parent plant. For example, grafting, cutting, bulbs, and runners

Budding

Asexual reproduction in which a part of the parent organism pinches off and forms a new organism, uneven division of cytoplasm
Only used by eukaryote ex. yeast, sponges

Conjugation

In bacteria, the direct transfer of DNA between two cells that are temporarily joined.

Regeneration

Stem cells differentiate to regrow all parts of the missing limb
Body part breaks off and in rare cases, grows into whole new organism
Ex. Invertebrates

Gene

A segment of DNA on a chromosome that codes for a specific trait

DNA

A macromolecule responsible for the inheritance of traits

Chromosomes

Storage units for tightly packed DNA which also carry the genes

Nucleus

A part of the cell containing DNA and RNA and responsible for growth and reproduction

Cell

The basic unit of structure and function in living things

G1 phase

stage of interphase in which cell grows and performs its normal functions

S phase

The synthesis phase of the cell cycle; the portion of interphase during which DNA is replicated.

G2 phase

Proteins are synthesized that will help the cell divide. At the end of interphase, the cell is ready to enter mitosis.

G0 phase

A nondividing state occupied by cells that have left the cell cycle, sometimes reversibly.

Prophase

first and longest phase of mitosis, during which the chromosomes become visible and the centrioles separate and take up positions on the opposite sides of the nucleus

Metaphase

second phase of mitosis, during which the chromosomes line up across the center of the cell

Anaphase

the third phase of mitosis, during which the chromosome pairs separate and move toward opposite poles

Telophase

the final phase of cell division, between anaphase and interphase, in which the chromatids or chromosomes move to opposite ends of the cell and two nuclei are formed.

cytokensis in plant cells

· Cell plate: divide their cytoplasm by forming a cell plate along the center line of the cell

Cytokenesis in animal cells

Two new daughter cells are formed, cleavage furrow

Centrioles

Cell organelle that aids in cell division in animal cells only

spindle fibers

form a protein structure that divides the genetic material in a cell

Chromatids

duplicate halves of a chromosome

nuclear membrane

A highly

metaphase plate

Plane midway between the two poles of the cell where chromosomes line up during metaphase.

cell plate

In a plant cell, midline of dividing cells. Becomes the cell wall eventually.

cleavage furrow

The area of the cell membrane that pinches in and eventually separates the dividing cell

Difference between plant and animal cells during the cell cycle

Animal cells

G1 checkpoint

checks for cell size, nutrients, growth factors and DNA damage

G2 checkpoint

Checks for: cell size, DNA replication, DNA damage.

M checkpoint

checks for chromosomes attached to the spindle (just before anaphase)

Cancer cell characteristics

Apoptosis and when does it happen

programmed cell death happens in cells when DNA is mutated or when cell signals aren't functioning

Internal factors that regulate cell division

checkpoints, cyclins, and kinases

External factors that regulate cell division

physical and chemical signals

CDK

Complex of cyclin and kinase key regulatory enzymes involved in cell proliferation through regulating cell

Cyclin

A cellular protein that occurs in a cyclically fluctuating concentration and that plays an important role in regulating the cell cycle. Constantly increases in Interphase until a threshold is reached which then it starts to bind with CDK.

MPF

Forms when cyclin binds to CDK and initiates the cell to perform mitosis

growth factors

Regulatory proteins that ensure that the events of cell division occur in the proper sequence and at the correct rate.

density

dependent inhibition

anchorage dependence

The requirement that to divide, a cell must be attached to a solid surface.

What is the purpose and organization of Signal Transduction Pathway

To help cells communicate

Ras protein

A type of proto

Apoptosis in cancer cells

Problems with cell signals that prevent cancer cells from doing apoptosis

necrosis

death of tissue

Tumors (Benign, Malignant, and Metastatic)

Benign

Angiogenesis

formation of new blood vessels (tumors create new blood vessels to help supply the growth of the tumor)

checkpoints in cell cycle

G1, G2, M

Regulatory process in the cell cycle

Checkpoints that look over the cell before entering each phase to make sure nothing is damaged

density

dependent inhibition (cancer cells)

anchorage dependence (cancer cells)

Cancer cells do not need a surface or substrate to grow

DNA repair genes

aka caretaker genes; responsible for the repair of errors in normal DNA replication

DNA polymerase

Enzyme involved in DNA replication that joins individual nucleotides to produce a DNA molecule

Telomerase

An enzyme that catalyzes the lengthening of telomeres. The enzyme includes a molecule of RNA that serves as a template for new telomere segments.

Telemeres

DNA at the tips of chromosomes which protect that ends of the chromosomes

tumor suppressor genes

make proteins that stop cell division and kill cells (p53)

p53

Molecule that prevents mitosis in cells with damaged DNA. Changes in its activity can result in cancer.

Proto

oncogenes

Oncogenes

genes that cause cancer by blocking the normal controls on cell reproduction, mutated proto

How many tumor suppressor gene alleles need to be mutated to form a cancerous cell?

2

How many proto

oncogenes alleles need to be mutated to form a cancerous cell?

Structure of DNA

DNA is like a ladder or spiral staircase. The outside is made of a sugar

Chargaff's Rule

A\=T and C\=G

semi

conservative replication

DNA replication steps

initiation, elongation, termination
1) Helicase

RNA

A single

Difference between RNA and DNA

Differ in terms of *structure and function*
*RNA*: *DNA*

Purines

Bases with a double

Prymidines

thymine, cytosine, uracil (single ring)

How do A and T bind differently from G and C

G and C have 3 bonds while A and T only have 2 bonds

Types of RNA

Messenger RNA (mRNA)
Transfer RNA (tRNA)
Ribosomal RNA (rRNA)

mRNA (messenger RNA)

RNA molecule that carries copies of instructions for the assembly of amino acids into proteins from DNA to the rest of the cell

rRNA (ribosomal RNA)

type of RNA that makes up the major part of ribosomes

tRNA (transfer RNA)

type of RNA molecule that transfers amino acids to ribosomes during protein synthesis

Transcription

RNA polymerase uses one strand of DNA as a template and adds free mRNA nucleotides in a single strand
to create mRNA for a particular gene. mRNA is then able to take the genetic code out of the nucleus and
into the cytoplasm.

Translation

mRNA from the nucleus goes to a ribosome. tRNA brings amino acids, matching up its anticodons with
the codons on mRNA. The amino acids link together to form a chain, a protein/polypeptide.

Codons

A three

Anti

codon

expressed gene

It is necessary for normal cell functioning and is "turned on"
to produce a protein.

Repressed/Suppressed gene

It is turned off in that cell and none of that protein is
made.

Meiosis

a type of cell division that results in four daughter cells each with half the number of chromosomes of the parent cell, as in the production of gametes and plant spores.

Meiosis steps in order

Prophase 1, Metaphase 1, Anaphase 1, Telophase 1, Prophase 2, Metaphase 2, Anaphase 2, Telophase 2

Mitosis vs. Meiosis

Mitosis: one division forming 2 identical cells (clones); Meiosis: two divisions forming 4 genetically different cells

independent assortment

each pair of homologous chromosomes lines up independently of every other pair at the equator of the cell during metaphase I

crossing over

homologous pairs exchange parts (prophase I)

Fertilization

Fusion of an egg and sperm cell produces a zygote

Gametes

sex cells

Zygote

a diploid cell resulting from the fusion of two haploid gametes; a fertilized ovum.

homologous chromosomes

Chromosomes that have the same sequence of genes but not the same genes, that have the same structure, and that pair during meiosis.

Tetrad

structure containing 4 chromatids that forms during meiosis

sexual vs asexual reproduction

Asexual reproduction generates offspring that are genetically identical to a single parent. In sexual reproduction, two parents contribute genetic information to produce unique offspring.

haploid cell

A cell containing only one set of chromosomes (n).

Diploid cell

A cell containing two sets of chromosomes (2n), one set inherited from each parent.

somatic cells

Any cells in the body other than reproductive cells

SNPs

variations in the DNA sequence that occur when a single nucleotide in the genome is altered, can affect how a person is affected by medicine

haplyotype

A group of genes that are inherited from a single parent