Science revison Flashcards
(34 cards)
What is the Cell Cycle
he life of a cell comprising
interphase and mitosis.
What is interphase
Preparation for mitosis in which
extra cell parts are made and DNA
chromosomes are replicated
(copied).
Mitosis
hen one cell divides into two
genetically identical daughter cells.
(I)PMATC
The stages of mitosis: interphase
(not mitosis), prophase, metaphase,
anaphase, telophase, cytokinesis.
Prophase
he membrane of the nucleus
breaks down and spindle fibres start
to form.
Metaphas
Spindle fibres fully form and
chromosomes line up across the
middle of the cell.
Anaphase
Chromosome copies separate and
move to each end of the cell.
Cytokinesis
The two new cells fully separate.
Telophase
A new membrane forms around
each set of chromosomes to form
two nuclei.
Cancer
When mitosis happens out of
control forming large lumps of cells
called tumours.
Growth
ncrease in size due to increased
numbers of cells.
Percentile
A measure of the growth of a
child that compares them to
other children of the same age.
90th percentile
A child is taller than 90% of
children of the same age.
50th percentile
Average for height/mass for the
age
Percentile
graphs
Graphs showing how
height/mass change with age
with different lines for each
percentile.
Cell
differentiation
When a cell divides by mitosis to
produce two different types of
cell (not two identical ones).
Specialised
cell
A cell special features designed
for a specific job.
Importance of
differentiation
in animals
To produce all the different
types of cell the body needs
such as red blood cells, fat cells,
nerve cells and muscle cells.
Plant growth
Cell division creates more cells,
elongation makes these cells get
bigger.
Meristems
Areas just behind the tips of
roots and shoots where cell
division and differentiation
happens.
Importance of
differentiation
in plants
To produce all the different
types of cell a plant needs such
as root hair cells and xylem cells.
Calculating
percentage
changes
% change = (final value – starting
value) / starting value x 100
Stem cell
A cell that can differentiate when it
divides, to produce two different
cells.
Embryonic
stem cell
A stem cell that can become any
kind of cell. Found in developing
embryos.
