Cell division Flashcards
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Adult stem cell
def
A type of stem cell found in specific locations in adults. Adult stem cells can only differentiate into a limited number of related cell types
Benign tumour
def
A tumour that is not cancerous and cannot spread to other areas of the body
Bone marrow
def
Soft tissue found inside bones that produces new blood cells
Cancer
A disease caused by normal cells changing so that they grow and divide in an uncontrolled way. The uncontrolled growth causes a lump called a tumour to form
Cancer cells are undifferentiated – they do not carry out their normal function.
Carcinogen
def
A chemical or other agent which causes cancer
Cell cycle
def
The events that lead to cell division and DNA replication
Chromosome
def
The structure made of DNA that codes for all the characteristics of an organism.
Clone
def
An organism that is genetically identical to another organism
Daughter cells
def
Cells formed from the division of a cell
Diabetes
A serious disease in which the body is unable to regulate blood sugar
Differentiation
def
When an unspecialised cell becomes a more specialised cell type
DNA
def
Deoxyribonucleic acid. The material inside the nucleus of cells, carrying the genetic information of a living being
Embryonic stem cell
def
A type of stem cell found in the embryo, capable of dividing into almost any cell type
Gene
def
The basic unit of genetic material inherited from our parents. A gene is a section of DNA which controls part of a cell’s chemistry - particularly protein production
Immune system
def
The body’s defence system against entry of any foreign body, including pathogens and agents such as pollen grains. The role of the immune system is to prevent disease
Ionising radiation
def
Radiation that is able to remove electrons from atoms or molecules to produce positively charged particles called ions
Malignant tumour
def
A fast-growing tumour that is cancerous and can invade and spread to other areas of the body
Meristem
def
A region in plant shoots and roots in which cells are dividing, and so are undergoing mitosis
Mitosis
Definition:
A type of cell division which produces daughter cells identical to the parent
In more detail:
Mitosis is a type of cell division in which a diploid body cell copies itself and finally divides into two identical diploid daughter cells. The daughter cells are clones of each other. Every base pair of their DNA is identical.
Multiple sclerosis
def
A disease which affects the brain and spinal cord and can make movement and communication difficult
Mutation
def
Arandom and spontaneous change in the structure of a gene, chromosome or number of chromosomes
Paralysis
def
The loss of muscle function in part of the body
Percentage growth chart
A chart used to compare the growth of a baby to the growth of other babies
Protein def and uses
Organic compound made up of amino acid molecules. One of the three main food groups, proteins are needed by the body for cell growth and repair
speciation
def
The formation of new and distinct species in the course of evolution
Stem cell
A cell found in foetuses, embryos and some adult tissues that can give rise to a wide range of other cells.
Stem cells are cells that have not undergone differentiation. A cell which has not yet become specialised is called undifferentiated.
Synthesise
def
Made or put together
Therapeutic cloning
Using cloning technology for medicinal purposes. One example is to use a person’s DNA to clone one of their organs for use in transplanting
Tumour
def
The lump of cells formed as a result of uncontrolled cell division
Ultraviolet
A high energy part of the electromagnetic spectrum associated with sunburn and skin cancer
Vacuole
def
A space within the cytoplasm of plant cells that contains cell sap
Zygote
def
A fertilised egg cell
Where does DNA exist?
For most of the time, DNA exists in the nucleus as thin strands.
How are chromosomes formed?
When the cells containing nuclei are ready to divide, the DNA copies itself then coils and condenses to form chromosomes.
What are chromosomes made of?
Each chromosome is made from a single molecule of DNA. Each section of this single molecule of DNA contains a code for the production of a particular protein called a gene.
How many chromosomes are in a (diploid) human cell contain?
Each human body cell contains 46 chromosomes. These can be arranged into 23 pairs. Each chromosome in a pair carries the same types of genes.