Download Chemical Elements in Cells

Science 8 – 9
Chemicals in Cells Notes
Name _________________________________
Date __________________________________
Why It Matters
If cells are the ______________________________________________ of living things, then what
substances are the basic building blocks of cells?
In what ways are the ______________________________________________ of cells similar to
those that make up other things around you?
We will learn how the substances that make up ______________________________________
differ from those that make up ________________________________________________________.
Elements
If you think of the air around you, you know that air is mixture of gases, including
_____________________________________. Oxygen and nitrogen are examples of
______________________________________.
_______________________________________ is a substance that cannot be broken down into
simpler substances.
The smallest unit of an element is called an _______________________________________.
The _________________________________________ found in living things include carbon,
hydrogen, oxygen, nitrogen, phosphorus, and sulfur.
Compounds
When two or more elements combine chemically, they form a
___________________________
Water is an example of a compound because it is made up of the elements
_____________________________________________________
The smallest unit of most compounds is called a _________________________________________
Each ______________________________________________________ is made up of two hydrogen
atoms and one oxygen atom.
Organic and Inorganic Compounds
Many compounds found in living things contain ___________________________________,
which is usually combined with other elements. Most compounds that contain
carbon are called _________________________________________________.
The most important groups of organic compounds found in living things are
________________________________________________________________________________________.
In organic compounds are compounds that _________________________________ contain the
element __________________________________________.
Carbohydrates
A carbohydrate is an _________________________________________________ made of the
elements carbon, hydrogen and oxygen.
_______________________________________________________ are examples of carbohydrates.
Sugars are produced during the ___________________________________________________ that
takes place in plants.
Foods such as __________________________________________________ are high in sugar content.
Sugar molecules can combine and form larger molecules called ________________________
Foods that come from ___________________________________ contain starch. For example
____________________________________________________________________________________________.
When we eat these foods, our bodies break down the starch into
___________________________________ and our cells use it for _________________________________
Carbohydrates are found in the plants ____________________________________ and in
________________________________________________________
Proteins
___________________________________________ are large organic molecules made of carbon,
hydrogen, oxygen, nitrogen and, sometimes, sulfur.
Foods high in protein include ______________________________________________________________.
Cells use proteins for many different things. For instance, protein forms parts of
_______________________________________________
Proteins also make up many of the ___________________________________________ within the
cell.
Certain cells in your body use proteins to ________________________________________________.
Amino Acids
Protein molecules are made up of smaller molecules called
_____________________________.
There are _________________________________________ but they can combine in different
ways to form thousands of different proteins.
Think of it like the ______________________________________ of the alphabet. They combine
to make thousands of words
Enzymes
An enzyme is a type of protein that speeds up a _____________________________________ in a
living thing.
Without __________________________________, many chemical reactions that are necessary
for life would either take too long, or not occur at all.
For example, enzymes in your ____________________________ speed up the
____________________________ of food by breaking down ___________________________into
______________________________________ in your mouth.
Lipids
_______________________________________ are fats, oils, and waxes. Like carbohydrates,
lipids are ____________________________________________________ made of carbon, hydrogen,
and oxygen.
Lipids contain even more _____________________________________ than carbohydrates.
Cells store _____________________________________in lipids for later use.
For example, during winter a dormant bear lives on the _______________________________
___________________________ within its cells.
Cholesterol
_____________________________________ is an important component of animal cell
membranes. You body requires a certain amount of this _____________________________.
Your _____________________________produces enough cholesterol to meet your body’s
needs.
However, many of the _____________________________________ also contain cholesterol.
Excess amounts of cholesterol can collect along the walls of __________________________
and _________________________________the flow of blood.
Foods that come from animals: such as ___________________________________________________
are high in cholesterol.
Nucleic Acids
____________________________ are very large organic molecules made of carbon, oxygen,
hydrogen, nitrogen, and phosphorus.
Nucleic acids contain the __________________________________ that cells need to carry out
all the ______________________________________ of life.
There are two kids of nucleic acids: _____________________________________________________
is the ___________________________________________ that carries information about an
organism that is passed from parent to offspring. The information in DNA also
__________________________________ the cell’s functions. Most of the DNA is found in the
_____________________________________ in the nucleus.
RNA plays an important role in the ___________________________________________________.
RNA is found in the _____________________________________________________________________
Water
Without ______________________________________, most chemical reactions within cells
could not take place.
Water molecules themselves take part in many _______________________________________ in
cells.
Water helps cells keep their _______________________________________________________.
Water also helps keep the _____________________________________________________ of cells
from changing rapidly.