AP Bio Unit 4 Vocab (Cell Communication and Cell Cycle)

Direct contact

Communication by cell-to-cell contact

Gap Junctions

The direct channel of communication for animal cells

Plasmodesmata

The direct channel of communication for plant cells

Hormones

Long-distance signaling molecules

Reception

A ligand binds to a receptor

Transduction

The extracellular signal is converted into an intracellular response

Response

A cell process is altered

Lingand

Chemical message in cell signaling

Second messengers

Small, non-protein molecules and ions that relay and amplify the first message Iigand)

GPCR (G-Protein Coupled Receptor)

A cell-surface receptor type important in animal sensory systems

Ligand-Gated Ion Channel

They are located in the plasma membrane and are important in the nervous system

Protein Kinase

Enzymes that relay & amplify the message by transferring a phosphate group from ATP to a protein

Protein Phosphatase

Enzymes that remove phosphate groups from proteins

cAMP (Cyclic Adenosine Monophosphate)

A small molecule made form ATP that activates protein kinases

Receptor

Proteins that recognize and bind to specific chemical messengers

Set points

Values for various physiological conditions that the body tries to maintain

Stimulus

A variable that will cause a response

Receptor/Sensor

Sensory organs that detect a stimulus

Effector

A muscle or gland that will respond

Homeostasis

The state of relatively stable internal conditions

Disease

When the body is unable to maintain homeostasis

Negative Feedback

Reduces the effect of stimulus

Positive feedback

Increases the effect of stimulus

Cell Cycle

The life of a cell from its formation until it divides

DNA

The primary genetic material of all living organisms. They are in chromosomes

Chromatin

A string of nucleosomes

Chromosome

A structure made of proteins and 1 DNA molecules that carries genetic information as genes

Histones

Proteins that, when combined with DNA, form nucleosomes

Nucleosomes

Made of histones & DNA, and can make chromatin

Centromere

The region on each sister chromatid where they are most closely attached

Kinetochore

Proteins attached to the centromere that link each sister chromatid to the mitotic spindle

Sister Chromatids

2 identical copies of a single chromosome that are joined by a centromere after DNA replication

Genome

All of a cell’s genetic information

Somatic Cells

Body cells with 2 sets of chromosomes

Gametic cells

Reproductive cells with 1 set of chromosomes

Checkpoints

Control points that regulate the cell cycle

Cyclins

Proteins that are important in internal cell cycle regulation

Cyclin-Dependent kinases

Enzymes that are important in internal cell cycle regulation

Growth factors

Hormones released by cells that stimulate cell growth

Contact Inhibition

Cell surface receptors recognize contact with other cells

Anchorage dependence

Cells rely on attachment to other cells or the extracellular matrix to divide

Mutation

DNA mutations are changes in the DNA

Tumor

A mass of tissue formed by abnormal cells

Malignant

A mass of cancerous cells that lose their anchorage dependency and can leave the tumor site

Benign

When cells are abnormal, but not (yet) considered cancerous

Metastasis

When cells separate from the tumor and spread elsewhere in the body

Apoptosis

Programmed cell death