Unit 2 - Producing cells

What are the phases of cell growth

First growth, synthesis, second growth and mitotic phase

What occurs in first growth of the cell

The cell produces new proteins, grows and carries out its normal tasks for the body, this phase ends when the cells DNA begins to duplicate

What occurs in the synthesis of the cell

The DNA molecules in the cells nucleus form exact copies of themselves

What occurs in the second growth of the cell

it is a short phase where the cell prepares for cell division

What occurs in the mitotic phase

The cell divides into two daughter cells hat W

What occurs in interphase

Chromosomes duplicate so that each daughter cell receives an identical ad complete set of genetic material

What are the stages of mitosis

Prophase, metaphase, anaphase and telophase

What occurs in prophase

Chromatin condenses into visible chromosomes and the layer around the nucleus breaks down. Microtubles begin to form from centrosomes and extend toward the centre of the cell

What occurs in Metaphase

Chromosomes line up along the middle of the cell

What occurs in anaphase

The microtubules shorten pulling the chromatids away towards opposite ends of the cell

What occurs in telophase

The nuclear envelope reforms and chromosomes unfold into chromatid

What occurs in cytokinesis

Begins separating the cell membrane into two separate daughter cells with identical chromosomes

What is differentiation

The process where cells become specialised by activating different genes to perform specific functions. Stem cells can divide to form more stem cells of divide and differentiate to form specialised cells

What are the different kinds of stem cells

Totipotent stem cells, pluripotent stem cells and multipoint stem cells

What is the function of a totipotent stem cell

Can form both the entire embryo and the supporting membranes

What is an example of a totipotent stem cell

An early embryo before the inner cell mass forms

What is the function of a pluripotent stem cell

Can form most tissues of the body but not supporting membrane

What is an example of a pluripotent stem cell

The inner cell mass of the blastocyst

What is the function of multipoint stem cells

Can form specific cell types within a particular tissue or system

What is an example of a multipotent stem cell

Blood stem cells forming blood stem cells

What is meiosis

A type of cell division that results in four genetically unique gametes with s3 chromosomes

What are homologous chromosomes

Matching pairs of chromosomes, the contain one strand from each parent that have the same genes in the same locations, they may carry different alleles

What is the role of mitosis

To produce two genetically identical

What does diploid mean

They have 23 pairs of homologous chromosomes

What are the phases of meiosis

Prophase 1, metaphase 1, anaphase 1, telophase 1, prophase 2, metaphase 2, anaphase 2 and telophase 2

What occurs in prophase 1

Chromosomes condense and become visible, and homologous chromosomes pair up. Crossing over then occurs, exchanging genetic material between homologous chromosomes

What occurs in Metaphase 1

Chromosomes line up along the centre of the cell and spindle fibres attach to the centromeres of each chromosome

What occurs in anaphase 1

Homologous chromosomes separate and move to opposite poles of the cell

What occurs in telophase 1

Two new cells are formed with half the original number of chromosomes, but still composed of two sister chromatids

What occurs in prophase 2

Chromosomes condense again

What occurs in metaphase 2

Chromosomes line up along the centre of each cell

What occurs in anaphase 2

Sister chromatids separate and move to opposite poles of the cell

What occurs in telophase 2

Four haploid daughter cells are produced, each with a single set of chromosomes and genetically different due to crossing over and random assortment