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Specialized Cells
YRHS Slides Research
Once an embryo is formed , the different cells develop into
specialized cells which are designed to perform specialized
function. Brain cells, muscle cells, epithelial cells, blood cells etc
are needed because one type of cell can not perform all the
functions just as one teacher can not teach all the subjects and
we need specialized teachers in high schools. Animals and
plants have their specialized cells and their structure is related to
their function. Single celled organisms don’t need to be
specialized as the cell body is small and it can communicate
freely with the environment and can carry all life functions
needed to survive.
Red Bood cells
Donut shaped ,
biconcave
Have hemoglobin to
Attract oxygen gas
Large surface area
and no nucleus for
greater absorption
Die in 120 days
because they don’t
have nucleus
White Blood Cell
. The head, containing genetic information and a nucleus, has an
enzyme to help penetrate the egg cell membrane.
•2. The middle section, immediately behind the head is packed with
mitochondria for energy.
•3. The tail or flagellum moves the sperm to the egg.
Sperm Cell
Xylem
Red Blood Cell
Nerve Cell
Pass sensory impulses from receptor to an effector
•1. Dendrites to make connections with other
neurones.
•2. Long axon or nerve fibre to carry the impulse to the
target organ.
•3. End plate forms a synapse with an effector (a
muscle or a gland).
•1. Packed with chloroplasts containing the
light absorbing pigment chlorophyll.
•2. Regular shaped, closely packed cells
forming a continuous layer for efficient
absorption of sunlight.
Example of
cell
Specific function
Specialised features suited to the
function
1. Tiny grain with half the genetic
information having been formed by
meiosis.
Pollen cell (male
gametes)
Fertilise the ovules
(female gametes)
•2. Have a hard protective outer coat to
survive bad conditions.
•3. Shape and surface of outer coat is
adapted to method of dispersal - eg smooth
and sticky for insect dispersal, larger
surface area for wind dispersal.
Image 5 - Guard Cells
Example of
cell
Guard cell
Specific function
Specialised features suited to the
function
•1. Regulate the size of leaf pore
Opens and closes leaf
•2. Change shape easily
pore
•3. Swell up when filled with water
Answer the following questions on a sheet of paper and hand it on Monday.
1. Why are complex organisms made up of specialized cells.
2. Think about your own body. List at least four activities that your body must
do to keep you alive and the specialized cells involved in each activity.
3. Choose two specialized cells mentined in question 2 and describe how their
structure is related to their function.
4. Every cell in your body came from single fertilized cell called zygote. What
does that tell you about the DNA difference s between one body cell and
another?
5. Do plants cells specialize the same way as animal cells? Use examples to
illustrate your answer.
6. Why do the single cells not show specialization?