cell divison

Question 1

Chromosomes and Mitosis

Answer 1

The nucleus of a cell contains chromosomes made of DNA molecules
each chromosome carries a large number of genes
chromosomes normally found in pairs

Question 2

Gene?

Answer 2

chromosomes present in cell nuclei made up off many different genes that encode many different proteins

Question 3

chromosomes

Answer 3

contain large number of genes and each gene tells how a specific protein should be made

Question 4

THE CELL CYCLE

Answer 4

Series of events involved in cell growth and cell division it involves mitosis which allows the growth repair and asexual reproduction of cells it involves……
initial growth stage -Extra ribosome mitochondria and other sub cellular structures are produced
cells chromosomes are replicated so there is two sets of the cells chromosomes

Mitosis- The two sets of chromosomes are pulled to two opposite ends of cell
then nucleus divides into two

Cell divides- the cytoplasm and cell membrane divide to create two identical daughters

Question 5

Mitosis #2

Answer 5

part of the cell cycle
chromosomes are pulled apart
nucleus divides
identical daughter chromosomes - mitosis ensures that bothe daughter cells have the same exact number of chromosomes and parent cell
this is an improtant process
for example the growth and repair of tissues and asexual reproduction

Question 6

do body cells or sec cells have more chromosomes?

Answer 6

body cells have twics as many chhromosomes as sex cells

Question 7

STEM CELLS

Answer 7

Stem cells are undifferentiated cells that have not yet been specialised to perform a special function however they can create more stem cells and differentiate to perform a different function

PLANT MERISTEMS- plant stem cells are found in the meristem tissue
plant stem cells can change into all types of plant cell throughout the life of a plant allowing the plants to grow through their whole lives

BONE MARROW - In human adults stem cells can be found in bone marrow as well as other organs and tissues
Adult stem cells differentiate into fewer cell types that stem cells in embryo used to replace dying cells and damaged tissues

EMBRYOS = Thhe stem cells in embryos can differentiate into most cell types to produce all cell types that will make up the organism

Question 8

uses of stem cells ?

Answer 8

can be used for many scientific medical and commercial purposes
stem cells may be able to replace damaged cells in the body
for example stem cells may replace the damaged cells that cause diabetes or paralysis
PLANT CLONES- plant stem cells can be used to quickly and cheaply produce cloned plants
This may HELP prtotect rare plant species from extinction and create large population of plant with special features such as disease resistant
THERAPEUTIC CLONING -produces an embryo with the same gene as the patient same DNA as the patient
Patients body will not reject the stem cells or body celss
ideal for use in stem cell medical treatment

Question 9

adavantages of stem cells

Answer 9

over 26000 people have been treate with stem cells for example for bone marrow cancer and allergies and also they eye corneo

Question 10

disadvantages of stem cells

Answer 10

VIRAL INFECTIONS - stem cell transplantation could transfer viral infections

ETHICAL BELIEFS some people disagree with the use of stem cells on religious ground
they believe that life begins at conception meaning that embryo is alive they view the use of embryonic stem cells as killing the embryo