HAP Pages 28-35 (Phase 1 Cell cycle)

10/28/25: First batch, 10/29/25: Second batch added

Cell Division

one cell splits into two daughter cells, including both mitosis and cytokinesis

Centromere

The narrow (center line) that holds the two sister chromatids together where the spindle fibers attach during cell division

Growth

An increase in cell size to prepare it for cell division.

What is mitosis?

process of cell division in which a single cell divides to produce two genetically identical daughter cells (AKA nuclear division) 

Interphase

The period before mitosis when the cell grows, does its job, and duplicates its DNA.

What happens in Prophase

Chromatin condense into chromosomes 

Metaphase

When chromosomes line up along the middle of the cell.

Anaphase

Where sister chromatids are pulled apart and moved to opposite sides of cell

Telophase

Chromosomes reach the poles, uncoil and form new nuclear membranes

Cytokinesis

When the cell’s cytoplasm divides to make two separate cells.

What is Chromatin

The form DNA takes when it’s wrapped around proteins(Happens in interphase)

Replication

The process of copying DNA so each new cell gets a complete set of genes.

Centriole

A small cylindrical structure in animal cells that helps organize spindle fibers during mitosis.

Spindle

A network of microtubules that attaches to chromosomes and pulls sister chromatids apart

DNA

The molecule that carries an organism’s genetic instructions in a code of bases

Unicellular

organism made of a single cell that performs all life functions on its own.

23

The number of chromosomes in a human gamete (sperm or egg), representing one complete set of chromosomes.

Cell Cycle

The repeating sequence of stages a cell goes through to grow and divide

Chromosomes are made up of what

2 daughter cells held together by a centromere

In Prophase, the _ _ disappears

Nucelar membrane

In Prophase the _ forms

spindle

In Prophase, the _ disappears

nucleus

In Telophase, the_disapears

Chromosomes

In telophase the _ and _ _ reform 

nucleoli, nuclear membrane

During Telophase, the _ furrow forms and disappears 

cleavage 

What are checkpoints? 

control mechanisms that ensure proper cell division and DNA integrity.

Cancer is a disease of _?

Mitosis

What has to happen in order for cancer to progress?

Checkpoints are mutated and don’t stop cell reproduction.

Apoptosis is

programmed cell death, (cell suicide)

HeLa cells are named after

Henrietta Lacks

What is so different about HeLa cells?

do not die after a set number of cell divisions.

In a healthy individual, the pH is

around 7.4

A _ mechanism allows the body to maintain a constant blood pH

homeostatic 

_ is when the body reaches and acidic state

acidosis

Acids can remove _ _ from blood cells

negative charge

On the pH scale 7 is

neutral

On the pH scale, anything above 7 is

alkaline

On the pH scale, anything below 7 is

acidic

What phase is this?

prophase

What phase is this?

metaphase

What phase is this?

anaphase

What phase is this?

telophase

What phase is this?

Cytokinesis 

Butterfly children are also known as this disease

Epidermolysis bullosa

What kind of cells are used in gene therapy?

Fibroblasts

What is a vector?

A modified virus used to carry the good gene

What are the 3 main steps of therapy?

1, collection, 2. culture, 3. administer

What is the goal of the gene therapy?

To deliver a working COL7A1 gene into the patient's cells.

What is RDEB?

A severe, recessive type of EB.

What gene is broken in RDEB?

The COL7A1 gene.

What protein is missing in RDEB

Type VII collagen.

What does "ex vivo" mean?

"Outside the body." Cells are treated in a lab, not inside the patient.

Why treat children early?

To prevent bad scarring and contractures (stiff joints).