Transcript of the cell.

I.
Macromolecules – giant molecules
A. Carbohydrates:
1. Compounds made up of carbon,
hydrogen, and oxygen.
2. Ratio: 1C : 2H : 1O
3. Also known as sugars.
4. Main source of energy for living
things.
5. Starches – complex molecules used to
store extra sugars.
6. Monosaccharide – single sugar.
Polysaccharide – many monosaccharides
joined together.
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B. Lipids:
1. Compounds made from Carbon + hydrogen.
2. Used to store energy + provide
waterproof coverings.
3. Categories are fats, oils, and waxes.
4. Do not dissolve in water.
5. Figure 2-14 page 46
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C.Nucleic Acids:
1.Compounds containing hydrogen, oxygen,
nitrogen, carbon, and phosphorus.
2.Made from nucleotides:
a)5 carbon sugar (ribose or
deoxyribose)
b)Phosphate group
c)Nitrogenous base:
1)Adenine
2)Cytosine
3)Thymine
4)Guanine
3.Transmits genetic information
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4. Figure 2-15 page 47
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D. Proteins:
1. Contains nitrogen, carbon, hydrogen,
and oxygen.
2. Made up of a long chain of amino
acids.
a)Figure 2-16 amino acid
3. Some control cell processes, form
muscle and bone, fight disease, and
are used for transport.
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E. Positives tests for macromolecules
1. Carbohydrates –
a)Pressure of sugar is known when
stained with iodine.
b)It stains very dark.
2. Lipids – fats + oils
a)Presence of lipid is known by
leaving a translucent spot on a
brown paper bag.
3. Proteins –
a)Presence of a protein is known by
using biuret reagent, turning the
solution a purple color.
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II. Cell Components
A. History
1. Robert Hooke, 1665
a) Viewed thinly sliced pieces of cork
(plant).
b) Saw “many little boxes”  small
rooms  cells.
2. Anton von Leeuwenhoek, 1675
a) Viewed living cells
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B. Cell Theory: 3 parts
1. All living things are made of 1 or more
cells.
2. Cells are the basic unit of life.
3. Cells come from pre-existing cells.
C. Cell Organization:
organelles (nonliving)
nucleus

cells (living)
muscle cell

tissues (group of same cells) muscles

organs (group of tissues)
heart

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organ system (group of different organs)

circulatory system
organism (different organ systems
combined) you
D. Cell organelles – a cell component that
performs specific functions in the cell.
1. Cell wall –
a)Surrounds the cell.
b)Gives support and protection; very
rigid.
c)Made of nonliving cellulose.
d)Found in plants, fungi, and most
bacteria.
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2. Cell membrane –
a)Outer covering in animal cells.
b)Just inside the cell wall in plants.
c)Not rigid; can change shape.
d)Selectively permeable membrane –
allows some substances to pass
through and others not.
e)Composed of 2 lipid layers.
Fig 7 – 15 page 184
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3. Nucleus –
a)Control center of the cell = brain.
b)Surrounded by nuclear membrane.
1)Has tiny nuclear pores used for
RNA (ribonucleic acid) to leave
the nucleus.
c)Chromosomes (DNA = deoxyribonucleic
acid) is located here.
d)Contains nucleolus (used to form
ribosomes).
e)Prokaryote – cell W/O a membrane
bound nucleus. Pro = no
f)Eukaryote – cell WITH a membrane
bound nucleus. Eu = true
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4. Ribosomes –
a)Found floating in cytoplasm and
attached to endoplasmic reticulum.
b)Composed of RNA.
c)Location of protein synthesis.
5. Endoplasmic reticulum E.R. –
a)Tubular passage way connecting all
parts of the cell.
b)Transportation system for proteins.
6. Golgi Apparatus –
a)Closely stacked membranes.
b)Receives proteins from E.R. and ships
to cell membrane.
c)“Post office” of the cell.
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7. Vacuoles –
a)Found in plants.
b)Storage tank for food, water,
wastes, and other materials.
8. Lysosomes –
a)Digestive activities within the
cell.
b)Can eat viruses, bacteria, dead or
injured cells, and old organelles.
9. Plastids –
a)Plant organelles used for storage.
b)Chloroplast – green, stores
chlorophyll.
1)Photosynthesis occurs here.
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10.Mitochondria –
a)Powerhouse of the cell
b)Supplies most of the energy for cell
use.
c)Respiration occurs here.
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III. Movement of materials in & out of a cell
A. Cell membrane
1. Semi-permeable- allows some substances
to pass through & others not.
2. Materials enter & leave by:
a) Passive transport
b) Active transport
B. Passive Transport- movement of
substances across an area without using
energy.
1. Diffusion-movement of molecules of a
substance from an area of greater
concentration to an area of lesser
concentration.
a) Examples of diffusion-food coloring
in water, kool-aid mix, perfume in
the air.
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b)Solute- any substance that is
dissolved.
c)Solvent- the substance that is doing
the solving.
Ex: ovaltine + milk= chocolate milk
(solute) (solvent) (solution)
d)Fig. 7-16 pg. 185
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2. Osmosis- movement of water, H2O, into
and out of the cell from a greater
concentration to a place of lesser
concentration.
a)A.K.A. diffusion of water
b)Maintains homeostasis- organisms
keep their internal conditions in a
biological balance with their
environmental.
1)Human cells must maintain the
following to live:
a) kept at a certain temperature
range
b) supplied with energy from
respiration
c) bathed in fluid
d) cleansed of the wastes
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c) 3 effects on cells by osmosis
1)Isotonic- concentration of solute
(dissolved substance) molecules
inside and outside a cell are equal.
a)Ex:
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2)Hypotonic- concentration of solute
molecules is lower outside the cell.
a)Ex:
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3)Hypertonic- concentration of solute
molecules is higher outside than
inside a cell.
a)Ex:
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d)Fig. 7-18 pg. 187
1)Hypo = O  swells up
2)Hyper= e  shriveled up 0
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d)Turgor pressure1)Plant cells have cell walls, which
are rigid.
2)Cannot fill endlessly, so pressure
builds with more water added.
3)This allows plants to “stand up.”
C. Active Transport- movement of any
substance across a cell membrane with
the use of chemical energy.
1.Sodium-potassium pump- sodium (Na+)
is pumped out of the cell and
potassium (K+)is pumped in.
a)Muscles & nerve cells work this
way.
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2. Endocytosis- large materials are engulfed
to enter the cell.
a) Ex: Phagocytosis- cytoplasm engulfs large
molecules.
3. Endocytosis- passage of large molecules
out of a cell.
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