1. INTRODUCTION TO BIOLOGY
Unit 1
INTRODUCTION TO BIOLOGY

2. I. INTRODUCTION TO BIOLOGY (pp.16-22)
A. What is Biology?
Biology means the___________.
Bio=____logy=________
Biology is the science that seeks to
understand the living world. So,
what makes something living?
study of life
life
study of

3. B. Characteristics of Life
1. Living things are____________.
a. A cell is the _______________________of life.
Living organisms are grouped by the number of
cells:
___________– single-celled organisms;
ex. Bacteria, amoebas
* ___________– organisms made up of more than one cell; ex. Humans, frogs, fish, insects, plants
made of cells
smallest working unit of life
Unicellular
Multicellular

4. B. Characteristics of Life
2. Living things____________________.
a. Two main ways to obtain energy:
*Some organism obtain energy directly from the _____and use it to make its own food, this process is called______________. Plants, some bacteria & protist use this process.
*Other organisms have to obtain their energy from the food they eat like us, other animals & fungi.
obtain & use energy
sun
photosynthesis

5. B. Characteristics of Life
obtain & use energy
2. Living things____________________.
b. One way to use energy:
* All organism uses its energy for __________- the combination of chemical reactions through which an organism __________
____________________as it carries out its life processes
Metabolism
builds up or
breaks down materials

6. B. Characteristics of Life
3. Living things ___________________________________
Organisms detect & respond to stimuli from their
environment.
b. Examples: ________________________
respond to their environment
Temperature
& light

7. B. Characteristics of Life
4. Living things maintain a ___________________________
Called: _____________- process by which organisms maintain a relatively stable internal environment
stable internal environment
Homeostasis

8. B. Characteristics of Life
grow & develop
5. Living things _______________
a. ________- all living things grow at least part of their lives, single-celled organism simple increase in size
b. _____________- describes _________________that take place during the lifetime of an organism
Growth
Development
physical changes

9. B. Characteristics of Life
6. Living things are based on a ______________________
a. Deoxyribonucleic acid or ______
b. The genetic code carried in DNA molecule determines the ____________of every organism on Earth.
universal genetic code
DNA
inherited traits

10. B. Characteristics of Life
reproduce
7. Living things __________
a. If this did not occur, _______would die out
b. Two ways:
* _______- new organism has a single parent; example- single-celled organism splits in half _____________________________
species
asexual
NO EXCHANGE OF GENETIC MATERIAL

11. B. Characteristics of Life
Living things __________
______- two cells (___________)
from different parents unite to form
an _______.
_____________________________
reproduce
Sexual
egg & sperm
embryo
IS AN EXCHANGE OF GENETIC MATERIAL

12. B. Characteristics of Life
As a group, ________________; this means, change over time.
living things evolve

13. II. THE CHEMISTRY OF LIFE (p. 37-38)
Organisms are composed of ______, which is anything that takes up space and has mass. All matter is composed of ________, pure substances that consists entirely of one type of ____.
matter
elements
atom

14. A. Elements 1. 92 naturally occurring elements 2. 25 essential to life
3. 4 making up 96% of living matter: _______________________________
4. atomic # = # of protons that element contains. Ex. Atomic # of C = 6
carbon,
hydrogen,
oxygen,
nitrogen

15. A. Atoms Nucleus a. center of atom
1. ___________-
a. center of atom
b. protons which have a _______charge
c. neutrons which are ________
positive
neutral

16. A. Atoms a. space surrounding nucleus
2. Electron cloud/orbital-
a. space surrounding nucleus
b. electrons in constant _______ in this space
c. electrons have a _________ charged; therefore attracted to the + charged nucleus
motion
negative

17. A. Atoms
3. Charge of Atoms
Have equal # of protons & electron so they are neutral

18. C. Isotopes –
protons
Atom with same # of _____________ but a __________________ of ______________
An example of an element that forms isotopes is __________.
Carbon-12 → the most common & ______ form of carbon; has __ protons and _ neutrons
Carbon-13 → __ protons & __ neutrons
Carbon-14 → __ protons & __ neutrons
3. Some are very unstable or __________________,
Useful in ______________ and ________________
different
neutrons
carbon
stable 6 6 7 6 6 8
reactive
research
medicine

19. D. Compounds
1. elements combined in __________ of atoms form compounds
2. held together by
3. Chemical formula
a. shorthand to show elements in a compound
b. ________ = 2 hydrogen atoms, 1 sulfur atom, 4 oxygen atoms for a total of 7 atoms
Ex. C6H6O6= __ carbon atoms, __ hydrogen atoms, __ oxygen atoms, total of ___ atoms
fixed ratios
chemical bonds
H2SO4 6 6 18 6

20. D. Compounds 4. Chemical Equation- a. recipe for making a compound
b. Reactants- what goes _______________
c. Products- substance that is _______________
d. Ex. 2H2 + O H2O; Reactant = _____________, Product = ____________
into the reaction
formed
H2 & O2
H2O

21. E. Chemical Bonds
1. Involves the valence electrons, what would be the ___________________
outermost electrons

22. E. Chemical Bonds 2. Ionic Bonds
a. One or more electrons are ___________ from one atom to another
Results in 2 oppositely charged
particles called ____________
** an atom that gains electrons has a ________ charge
**an atom that losses electrons has a ________ charge
transferred
IONS
negative
positive

23. E. Chemical Bonds 2. Ionic Bonds
c. Attraction between oppositely charged ions forms ionic bonds
d. Ex. NaCl or table salt
e. Weaker bonds than covalent

24. E. Chemical Bonds 3. Covalent Bonds a. electrons are being _______
b. results in very stable compounds called ______________
C. Ex. _________________________
D. Stronger bonds than ionic
shared
MOLECULES
Water,
Glucose,
DNA

26. WATER (pp. 40 – 43)
Water is the most ________________ and abundant substance on Earth. Cells are made up of mostly water and most cells are_______ by water. The importance of water is largely due to its unique characteristics, which all directly relate to one very important property of water Water is polar.
essential
surrounded

27. A. Polarity
a. ______________ of electrons in molecules formed with covalent bonds
b. How this works: A closer look at a water molecule:
1. oxygen has __ protons in nucleus & each hydrogen has ___ proton in their nucleus
Unequal sharing 8 1

28. A. Polarity 10
b. ____ shared electrons will be more attracted to the more ________ charged oxygen nucleus; thus orbiting around the oxygen end of the molecule just about all the time
c. The oxygen end will have a slightly _________ charge
d. The hydrogen ends will have a slightly _______ charge
e. Not true charges because the electrons are not transferred; just _________________
positively
negative
positive
shared unequally

29. 2. Hydrogen “Bonds” a. Not a ____ bond- does not form a ____ compound
b. Attraction between _________ molecules; like water
true
new
two polar

30. 2. Hydrogen “Bonds”
c. attraction between slightly ________ charged hydrogen end of one polar molecule and the slightly _________ charged end of another polar molecule.
d. EX. In water: forms between positively charged __ end of one water molecule and the negative end of another water molecule
positively
negatively H

31. 3. Hydrophilic vs Hydrophobic
a. Polar molecules are attracted to other _______ molecules,
Any molecule attracted to water is described as ________________
b. Non-polar molecules are attracted to_____________________________.
Molecules repelled by water are described as________________.
polar
hydrophilic
Non-polar molecules
hydrophobic

32. B. Properties
Polarity gives water some unique properties important in maintaining __________________
homeostasis