Transcript Animal Cells

Animal & Plant Cells
Noadswood Science, 2012
Saturday, April 9, 2016
Animal & Plant Cells
 To know the structure of animal and plant cells, and the function
of each part
Specialised cells
e.g. gametes
Cells
 A cell is the basic building block for both animals and plants
 Cells are extremely small (we need a microscope to see them)
 Animal cells have some basic properties (although this is a
basic generalisation - we can get extremely specialised cells)
 You need to learn the parts which make up our animal cell…
Animal cells - stained
Animal Cell
 Draw an animal cell, labeling each of the key parts and
identifying their function
Animal Cell
Animal cells contain:  Cell membrane
 Cytoplasm
 Nucleus
 Mitochondria
 Ribosomes
Ribosomes (small bodies on
the endoplasmic reticulum)
Cytoplasm
Nucleus
Cell membrane
Mitochondria
Functions
 You must also know the functions of the parts which make up
the animal cell
Part
Function
Nucleus
Contains genetic material, which controls the activities of the cell
Cytoplasm
Most chemical processes take place here, controlled by enzymes
Cell membrane
Controls the movement of substances into and out of the cell
Mitochondria
Most energy is released by respiration here
Ribosomes
Protein synthesis happens here (attached to the endoplasmic reticulum)
Plant Cell
 Draw a plant cell, labeling each of the key parts and identifying
their function
Plant Cell
Plant cells contain:  Cell membrane
 Cytoplasm
 Nucleus
 Mitochondria
 Ribosomes
 Cell Wall
 Vacuole
 Chloroplasts
Cell membrane
Mitochondria
Ribosomes
Cytoplasm
Nucleus
Chloroplast
Cell wall
Vacuole
Functions
Part
Function
Nucleus
Controls what happens in the cell (but it is not a ‘brain’)!
Cell Membrane
Controls what substances can enter and exit the cell
Cytoplasm
Where chemical reactions take place (jelly-like substance)
Mitochondria
Most of the cells energy is released here via respiration
Ribosomes
Protein synthesis occurs here
Chloroplasts
(Plants only)
Where photosynthesis occurs (contain chlorophyll (which is green))
Vacuole
(Plants only)
Contains cell sap (a solution of sugar and salt) helping with rigidity
Cell wall
(Plants only)
Made of cellulose, which gives support to the cell
Microscopes Practical
 Using the microscopes prepare and view a slide of your cheek
cells:  Swipe a cotton bud on the inside of your cheek and smear
onto a slide
 Add a drop of methylene blue (stain)
 Lower the cover slip
 Place the cotton bud into the disinfectant
 Draw your slide and label it, including its magnification
Microscopes
There is a procedure of 8 steps you need to follow to use a microscope correctly…
1.
Place the smallest objective lens (the smallest
lens) over the hole in the stage
2.
Turn the coarse focusing wheel to make the gap
between the stage and the objective lens as
small as possible
3.
Place a slide on the stage, and secure with the
clips. The slide contains what you want to see
(your specimen)
Microscopes
4.
Adjust the light source so light goes up through the
stage
5.
Look into the eyepiece lens
6.
Turn the coarse focusing wheel slowing, until your
specimen is in focus
Microscopes
7.
To see your specimen in more detail, turn the next
largest objective lens over your specimen
8.
Use the fine focusing wheel to get your image into
focus again - do not use the coarse focusing wheel
- this can break your slide!
Magnification
 Magnification is easy to work out - it is the eyepiece lens x the
objective lens:
Magnification = magnification eyepiece lens x magnification
objective lens
E.g.
eyepiece lens = 10x
objective lens = 60x
Magnification = 10 x 60
= 600x magnification
Cell Size
 All living things are made of cells but you cannot see them with
the naked eye so scientists use microscopes to magnify the
image
 The largest cell in the human body is
the ova (egg cell) which measures
approximately 0.1mm (smaller than a
full stop)
 The smallest cell is the sperm
measuring 0.06mm in length from
head to tail and the width of the head
is just 0.0025mm
Measurements
 The average animal cells is 0.02mm across whilst the average
plant cell is 0.04mm across
 Conversion of units: -
 Millimeters (mm) = 1m x10-3
 Microsmeters (μm) = 1m x10-6
 Nanometers (nm) = 1m x10-9
 Cell surface membranes are 0.00001mm thick – work out what
this is this in micrometes and nanometers…
0.01μm or 10nm