Cell Structure (+ microscope) Flashcards
Ch 7
Two types of microscopes are?
electron and compound
Light microscope is an example of which microscope type?
compound
How is the total magnification of the image calculated?
multiply the power of the two lenses
If given the size magnified and given total magnification, how do you find actual size of cell?
magnified divided by total magnification
Whats the function of the eyepiece lens?
magnifies the image
Whats the function of the nosepiece?
holds objective lenses
Whats the function of obejctive lens?
magnifies the image, 3 levels eg: x4, x10, x40
Whats the function of the clips?
holds slide in place
Whats the function of the stage?
supports slide once placed on
Whats the function of the condenser?
focuses light onto the slide
Whats the function of the diaphragm?
adjusts the amount of light shining on the slide
Whats the function of the light/mirror?
supply light to the slide
Whats the function of the stage height adjuster?
let stage be moved up and down
Whats the function of the coarse focus knob?
approximately focusing
Whats the function of the fine focus knob?
for precise focusing
What does TEM and SEM stand for?
transmission electron microscope
scanning electron microscope
What does continuity of life mean?
all cells arise from other pre-existing cells
Ultrastructure definition?
the structure of a cell seen under an electron microscope
Protoplasm definition?
all living parts of a cell
Cytoplasm definition?
living material in a cell, outside the nucleus
Name the parts of the cell present in animal and plant cells.
cell membrane
cytoplasm
mitochondria
ribosomes
nucleus
nucleolus
nuclear pores
DNA
vacuole
Name the 2 parts in plant cells only.
chloroplasts
cell wall
Definition of prokaryotic?
do not have a nucleus or membrane-bound organelles
Definition of eukaryotic?
have a nucleus and membrane-bound organelles
Example of a prokaryote?
bacteria
Example of a eukaryote?
animals
plants
fungi
protista
Unicellular means?
a single celled organism
Example of something unicellular?
bacteria, amoeba
Multicellular means?
more than one cell
Example of something multicellular?
plants, animals
Give 3 differences between plant and animal cells.
CELL WALL
plants have, animals do not
CHLOROPLASTS (CHLOROPYLL)
plants have, animals do not
LARGE VACUOLE
plants have, animals do not
What is a cell?
is the smallest unit of living matter that exhibits the characteristics of of life
The cell wall is made of what? What is it an example of?
cellulose, which is a structural polysaccharide
Is the cell wall not permeable, semi permeable, fully permeable…?
it is fully permeable
Cell wall function?
gives strength and support, prevents bursting
Where is the cell membrane located for (a) animal cells and (b) plant cells?
a) surrounding cytoplasm
b) found between the cytoplasm and cell wall
What is cell membrane composed of? What is it called?
phospholipids and proteins
the bilayer
Is the cell membrane not permeable, semi permeable, fully permeable…?
selectively/semi - permeable
Give 4 functions of the cell membrane
- retains cell contents
- gives support to animal cells
- has recepters
- controls movement of substances in and out of the cell***
What are vacuoles?
membrane bound sacks within cytoplasm (surrounded by a membrane)
Vacuoles are surrounded by what and within what?
surrounded by a membrane,
within cytoplasm
What do vacuoles do for plants?
gives cells strength
storage for food/waste
Permanent vacuoles are always found in _____ cells, temporary vacuoles can be found in some _____ cells but not all.
plant
animal
What do vacuoles store?
water and sugar
Vacuoles remove what?
waste
Are vacuoles larger or smaller in plant cells? (compared to animal cells).
larger
What is the control centre of the cell?
nucleus
Nucleus contains?
DNA, RNA
Nucleus is surrounded by what with what?
by a nuclear membrane with nuclear pores
Nuclear membrane with nuclear pores allows the passage of?
some molecules into and out of the nucleus
Ribosomes are made in?
nucleolus
When are chromosomes called chromatin?
when they are elongated and not dividing
Where is DNA present in the nucleus?
the chromosomes
What are organelles?
structures with membranes that carry out specific functions in a cell
What does mitochondria supply to cells?
energy
The mitochondira has cristae (infoldings), what does this allow?
increased energy production
Why can’t you see mitochondria with a light microscope?
too small to be seen
Where are there large amounts of mitochondria, why?
liver and muscle cells as they require a lot of energy
Does mitochondria contain DNA?
yes (each mitochondrion has its own loop of DNA)
Where is the site of respiration in a cell?
mitochondria
what organelle is the site of photosynthesis (in plant cells)?
chloroplast
What is the name of the pigment in chloroplast? What colour is it?
green pigment called chlorophyll
What does chlorophyll do?
absorbs light energy, giving plants their green colour
Can you see chloroplast under a light microscope?
no, too small to be seen
Does chloroplast contain DNA?
yes
Ribosomes are the location for what?
protein synthesis
Ribosomes are composed of?
RNA and proteins
Function of mitochondria*?
releases energy from glucose
Function of ribosomes*?
make proteins
Chloroplast function*?
photosynthesis