The Cell Cycle – Kyana Ok

What are the two phases of the cell cycle?

Interphase and Mitotic phase

What is the G₁ phase?

The cell grows and makes protein

What is the S phase?

The cell doubles/replicates

What is the G² phase?

The cell continues to grow and make proteins.

What is the mitotic phase?

It is the cell division

What is a chromatin?

One long continuous strand of DNA. It consists of numerous genes, regulating information, and some protein

What are chromosomes?

Bundles of chromatins.

What is the cell cycle controlled by?

Chemical control system

What is are external regulations?

Signals that come from outside of the cell (hormones, nutrients, etc.)

What are internal regulations?

Critical points where it signals the cycle to “stop” and “go”

What does the cell division process begin with?

A fertilized egg (zygote)

What can cell division create?

It can create many new identical cells

What is differentiation?

A process that creates special structures and functions

What can specialized cells become?

Tissues → Organs → Organ systems

What is an organism?

One individual/member of species

What is an organ system?

Distinct set of organs that work together for a common function

What is an organ?

Several types of tissue that work together for a common function

What is a tissue?

A group of identical cells that work together for a common function

What is a cell

The most basic unit of life. There are 6 characteristics of life.

What is a cell cycle?

It is a repeated pattern of growth in the cell

What are the main purposes of the cell cycle?

It grows and repairs

What is apoptosis?

Programmed cell death

What is cancer?

The uncontrolled cell division

What are tumors?

Clumps of cells that divide uncontrollably.

What are malignant?

Cancer cells that can breakaway from the tumor and be carried to parts of the body or organ and form more tumors

What are benign?

Abnormal cells, typically remain clustered together

What are carcinogens?

Cancer-causing agents. They can mutate DNA

What is the prophase?

The nucleus disappears, and the chromosomes become visible

What is the metaphase?

The chromosomes line up in the middle

What is the anaphase?

The chromatids split

What is the telophase?

New nuclei form around the chromosomes

What is cytokinesis?

The cell physically splits

What are the checkpoints?

G₁, S, G₂, Metaphase

What are the conditions checked for the checkpoint G₁?

The cell size, nutrients, and no DNA damage

What are the conditions checked for the checkpoint S?

No DNA damage or replication errors?

What are the conditions checked for the checkpoint G₂?

No DNA damage, complete DNA replication, and cell size with enough parts

What are the conditions checked for the checkpoint Metaphase?

It makes sure the chromosomes are in the middle

What is a cyclin?

A regulatory protein that accumulates and degrades.

What is the analogy for a cyclin?

The key that starts the engine

What is a CDK?

Enzymes that don’t become active until they bind with cyclin

What is the analogy for a CDK?

The engine – powerful, but needs a key

What are cell cycle checkpoints?

Tells the cell cycle when to stop and go

What is the analogy for cell cycle checkpoints

The traffic light – ensure it’s safe to move around

What are the normal function for Proto-oncogene

Promotes normal cell growth and division

What is the cancer-causing mutation type of a proto-oncogene

Gain of function (overactive)

How many mutations are needed for a proto-oncogene?

1 mutated copy

What is the car analogy for a proto-oncogene

Gas pedal stuck down – one stuck pedal is enough to speed out of control

What is the normal function of a tumor suppressor gene?

It slows cell growth, repairs DNA, and triggers cell death

What is the cancer-causing mutation type of a tumor suppressor gene?

Loss of function (inactive)

How many mutations are needed for a tumor suppressor gene?

2 mutated copies

What is the car analogy for a tumor suppressor gene?

Both brakes fail – One working brake still slows the car, but both must fail to lose control.