this ppt helps you to know about atoms and molecules......................................................................................................................................................................................................................................

1. STAREX INTERNATIONAL SCHOOL
NAME :- SANYAM
CLASS :- IX B
ROLL NO:- 29
TOPIC :- ATOMS AND MOLECULES
SUBJECT:- SCIENCE

2. ATOMS AND MOLECULES

3. • See pgs. 26-41
CHEMISTERY:-
–Science that deals with structure of
matter
–Refers to the physiology side of this
class
MATTER:-
-3 types (solid, liquid and gas)
COMMON CHEMISTRY TERMS

4. • ATOM:-
–Smallest stable
unit of
matter
• Three subatomic
particles:
–Protons:
–Neutrons:
–Electrons:
ATOMS

5. • Can you calculate the number of protons,
neutrons and electrons for ANY element on
the periodic table?
• REMEMBER:
• Protons = Atomic #
• Electrons = # of protons
• Neutrons = Atomic Mass # minus Atomic #
• If protons are not equal to electrons the atom
is now known as an ion
• Cation = (+) and Anion = (-)
ATOMS (CONTINUED)

6. • Three types of chemical bonds:
– Ionic bonds: between ions
– Covalent bonds: shared electrons
– Hydrogen bonds: between two
molecules
CHEMICAL BONDS (CONTINUED)

7. • Nutrients: essential elements and molecules
normally obtained through diet
• Metabolites: all molecules that can be processed
and broken down by chemical reactions in our
bodies
– Organic compounds:
• C and H form basis
– Inorganic compounds:
• Usually do NOT contain C and H atoms as primary
structure
• Most important in body:
– Carbon dioxide (CO2)
– Oxygen (O2)
– Water (H2O)
– Inorganic acids, bases and salts
INORGANIC COMPOUNDS

8. Inorganic Compounds
(continued)
• Water accounts for most of
your body weight.
• Proteins, the key structural and
functional components of cells, and
nucleic acids, which control cell
structure and function, work only in
solution with the UNIVERSAL Solvent
known as Dihydrogen oxide (water).

9. Acid/Base Terminology and the pH
(parts per Hydrogen) Scale
 Hydrogen ions (H+) = “Chemical Bad Boy”
Highly reactive
 Break chemical bonds
 Change shape of complex molecules
 Disrupt cell and tissue functions
Must be regulated precisely
 pH: concentration of H+ ions in body fluids
 pH Scale: 0-14
Neutral: solution with pH of 7
Acidic: solution with pH below 7
Basic: solution with pH above 7
pH of pure water = 7
pH of blood = 7.35-7.45

10. • pH of blood = 7.35-7.45
• QUICK QUIZ: So is blood neutral, acidic
or basic?
– Basic or otherwise known as ALKALINE!
• Large changes in pH of blood can be
damaging to cells, tissues and functioning
– Acidosis: low blood pH (below 7.35)
• Below 7 = coma
– Alkalosis: high blood pH (above 7.45)
• Above 7.8 = uncontrollable, sustained skeletal muscle
contractions

11. BIOCHEMISTRY
Living things are mainly composed of
four kinds of MACROMOLECULES:
Proteins, Nucleic Acids, Carbohydrates
and Lipids.

12. PROTEINS
• Structurally helps build
certain areas of the body
that need extra toughness
or strength such as Keratin
in nails and hair or
cartilage.
• Chemical messengers to
keep the brain in contact
with the rest of the body.

13. NUCLEIC ACIDS
• Stores information and considered
the body’s blueprint.
• Comes in two varieties, DNA or RNA

14. CARBOHYDRATE
 Provide energy storage
Simple carbs are known as
monosaccharide's or sugars
Complex carbs are known as
polysaccharides or
starches
Composed of
Carbon and
Water.

15. LIPIDS
Long term storage otherwise known as
fat
Composed of fatty acids and glycerol
Saturated fat= has single carbon
bonding
• Unsaturated fat=
has double bonded
carbons

16. THE END