Unit 1 KA1 - differentiation Flashcards
what is cellular differentiation?
the process by which a cell expresses certain genes to produce proteins characteristic for that type of cell.
give an example of cellular differentiation.
a basic animal cell becoming specialised into a goblet cell in the trachea.
this goblet cell then expresses the genes for making proteins found in mucus.
how does a cell become specialised?
by the switching on and off of genes.
give examples of differentiated cells.
muscle cells, goblet cells, nerve cells and red blood cells.
what is a stem cell and what can it do?
they are unspecialised cells in animals that can continue to divide to make copies of themselves and differentiate into specialised cells.
wat are the two types of stem cells?
embryonic and tissue.
embryonic stem cells are described as …………
pluripotent.
where are tissue stem cells found?
the brain, skin, testicles, breast, bone marrow, intestines, muscles and cornea.
tissue stem cells are described as ……………., which means they can only produce the ……… of cell types found in a …………… …………… type.
multipotent, range, particular tissue.
what is a somatic cell?
any cell in the body other than cells involved in reproduction.
how do somatic cells form more somatic cells?
dividing by mitosis.
each somatic cell contains ….. chromosomes and is ……..
46, diploid.
the cell that produces gametes is a …………
germline stem cell.
where are germline stem cells found?
ovaries and testes.
germline stem cells can divide by……….. to produce ……. germline (…………) cells.
mitosis, more, diploid.
germline stem cells can divide by ……. to produce gametes (…………) cells.
meiosis, haploid.
name the first and second divisions of meiosis.
homologous chromosomes separated, chromatids separate.
cancer cells ………. excessively to produce a mass of ……….. cells called a …………
divide, abnormal, tumor.
tumour cells do not ………. to …………. signals and may ……… to ……….. to each other.
………….. tumours form if ………… cells ……. to attach to each other so they ………… through the body.
respond, regulatory, fail, attach, secondary, cancer, fail, spread.
give examples of the therapeutic use of stem cells.
corneal transplants, regeneration of damaged skin.
in research, stem cells can be used as ……… to study how ………. develop and to ……… drugs.
model cells, diseases, test.
stem cells research provides info on how cell processes work such as;
cell growth, differentiation and gene regulation.
give an ethical issue surrounding the use of embryonic stem cells.
results in destruction of the embryo .
what are differentiated cells?
Cells that have become specialised to carry out their various specific functions.
How many chromosomes are found in somatic cells?
46
Name the process by which germline cells produce more germline cells.
mitosis.
Name the process by which germline cells produce gametes.
meiosis.
List three diseases that could potentially be treated using transplanted cells originated from embryonic stem cells.
Any three from: diabetes; Duchenne's; muscular dystrophy; heart disease; Parkinson's disease; traumatic spinal cord injury; vision and hearing loss.
give an example of a therapeutic use of stem cells.
burn victim patients, where the epidermis and the delicate tissue of the dermis are damaged, are often treated using skin grafts of their own skin.
To prepare a graft, a section of healthy skin is removed from an undamaged part of the patient’s body. This is then grown in special nutrient solutions, which encourage the epidermal stem cells to divide, and a graft for the burn site is produced from this culture.
