SBI3C Unit 1: Cellular BiologyJ. Lovett

Chapter 1 – Molecules in Cells: Building Blocks of Life (1.1 to 1.6)

What is a cell?

The cell is the ________________, functional, and biological unit of all ______________

Most cells are too ________to see with the naked eye

Cells are made up of ___________ and _________________

How big is a cell? Let’s compare…

https:// www.youtube.com/watch?v=t4Tst9DZFPI

The Cell Theory

The Wacky History of the Cell Theory

https :// www.youtube.com/watch?v=4OpBylwH9DU

What is the Cell Theory?

1. All living organisms are composed of _________ or __________ cells

2. The cell is the most ___________ unit of life

3. All cells come from pre-existing _____________

Building Blocks of Cells

*We will learn about organelles soon but not today!

What are elements and atoms?

A chemical _______________ is a pure substance that cannot be broken down into another substance

Examples: _________________, ____________________, ________________

Fun fact: Carbon, hydrogen, oxygen and nitrogen account for nearly ______% of the human body!

Other essential elements are ________________

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Atoms

Smallest unit of elements

Molecules

Made from atoms

Organelles*

Made of molecules

Cells

Made of organelles*

SBI3C Unit 1: Cellular BiologyJ. Lovett

Examples: _______________, __________________, _________________

An ____________ is the smallest possible “piece” of an element

Atoms are composed of ______________, _____________ and ______________

What are compounds and molecules?

A _________________ is a pure substance made up of _________ or more chemically combined elements.

Example: ______________ is made up of hydrogen and oxygen (H2O)

Example: ______________________ is made up of carbon and oxygen (CO2)

Most chemical compounds in biological systems exist as _______________

A _______________ is a particle that results when two or more atoms are joined by _____________________ _____________

A covalent bond forms when two atoms ________________ electrons

What is an ion?

An ion is an ______________ that has gained or lost _________________

Electrons have a negative charge, so if an atom loses electrons it will become _________________ charged. We call this a ______________

If an atom gains electrons, it will become _______________ charged and we call this an ______________

Ions take part in many ________________________ processes. For example, the beating of your heart and sending messages to and from your brain.

Ions that dissolve in the body’s fluids are called ____________________________

When you perspire you lose ________________

Here are examples of some ions that you lose when you perspire:

Na+ (sodium, +1 charge, which means it is a _________ and it _______electrons)

Cl- (chlorine, -1 charge, which means it is a __________ and it _______electrons)

Chemical Reactions

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SBI3C Unit 1: Cellular BiologyJ. Lovett

Life exists because of the chemical reactions that are constantly occurring in _______

In a chemical reaction, the ___________ of elements and compounds are rearranged to become different substances

During this process, some chemical bonds are _______________ and some are _______________

When bonds break, ______________is absorbed

When bonds form, energy is ____________

The Most Important Molecule in the World

No organism on Earth can live without _______________

The chemical formula for water is ____________

It is made up of two _______________ atoms and one _____________ atom which are held together by _________________ bonds

Water molecules are like tiny magnets, they have a slightly ________________ end and a slightly ________________ end

The negative and positive ends attract each other, causing water molecules to bond with each other through something called ______________ _______________

Molecules that have positive and negative ends are called ____________ molecules

Water has many unusual properties as outlined below

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SBI3C Unit 1: Cellular BiologyJ. Lovett

More about Water!

Water is sometimes called the __________________ solvent because it has the ability to dissolve many substances

It does not dissolve everything though!

______________________ substances dissolve well in water, such as ___________ and _________________

______________________ substances do not dissolve well in water, such as _______________ and _________________

Fun Fact! ___________________ means “water-loving” and __________________ means “water-fearing”

When we wash our dishes or wash our hands, we usually use some sort of soap because water alone cannot remove the grease and oils from our hands. This is because grease and oil are ___________________.

Some laundry detergents contain both hydrophilic and hydrophobic ends so that it can dissolve the oils and grease from our clothes, but also dissolve in water and go down the drain

Let’s Recap!

https://www.youtube.com/watch?v=HVT3Y3_gHGg

Water Solutions

Water solutions can be _______________, _______________ or ______________

An _________ is a substance that increases the number of positive hydrogen ions (H+) when it is added to water

Example: ______________ is an acidic liquid and it tastes sour

A ______________ is a substance that increases the number of hydroxide ions (OH-) when it is added to water

Example: ________________ is a basic liquid and it feels slippery

A solution where the number of H+ ions and OH- ions are equal is called _____________

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SBI3C Unit 1: Cellular BiologyJ. Lovett

Example: ____________________ is a neutral substance

The _________ scale is used to measure how acidic or basic a solution is

It ranges from 0 to 14, with 0 being the most acidic and 14 being the most basic

Pure water has a pH of ______ because it is neutral

How does the pH scale relate to cells?

Cells and their contents can only _______________within certain pH ranges

For many cells, the normal pH is close to _____, or ___________

Straying too far from the normal pH can be ____________ for a cell

Luckily, cells come equipped with a _________________ _______________

This system helps keep the pH within a _________ range

If the pH gets too high, it means it is too __________ and there are too many _______ ions. To counteract this, the buffer system releases more ______ to lower the pH and make it more __________

If the pH gets too low, it means it is too __________ and there are too many _______ ions. To counteract this, the buffer system releases more ______ to increase the pH and make it more __________

Without this system, the cell could die

What is a Macromolecule?

Our skin, eyes, bones, muscles and all of our other organs contain specialized that they need in order to _______________

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SBI3C Unit 1: Cellular BiologyJ. Lovett

These specialized molecules are known as ________________ compounds

Some organic compounds are made up of hundreds or even thousands of atoms

These large molecules with complex structures are known as ______________________

Many macromolecules are called _____________________

A _________________ is a long chain-like molecule composed of many smaller molecules

The smaller molecules that link together to form polymers are called _______________

Note: “mono” means one and “poly” means many or more than one

The Four Important Types of Macromolecules

All organisms get their macromolecules from ______________

The four main types of macromolecules are:

1. __________________________

2. _____________ (also known commonly as “fats”)

3. ________________

4. ________________ ___________

The chart on the following page summarizes the main types…

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SBI3C Unit 1: Cellular BiologyJ. Lovett

Carbohydrates

Carbohydrates are an important source of ______________ for humans

Chemically speaking, carbohydrates are substances composed of _____________, _________________ and ________________ atoms

In general, a carbohydrate is a macromolecules that includes ________________ and _________________

There are three main types of carbohydrates:

1. _______________________________ (“mono” means one)

2. _______________________________ (“di” means two)

3. _______________________________ (“poly” means many)

Monosaccharides

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SBI3C Unit 1: Cellular BiologyJ. Lovett

Monosaccharides are the ________________ of the carbohydrates

They are also known as __________________ or ________________ sugars

They are the building blocks of more complicated ________________________

In solid form, monosaccharides are _____________________ ______________ and have a ____________ taste

The most familiar and important monosaccharide is _____________________

____________________ provides our bodies with immediate __________________

Other important monosaccharides include:

____________________________, found in plants

____________________________, found in dairy products

Disaccharides

Disaccharides are two _________________________ molecules bonded together

When you hear the word “sugar”, you probably think of the grainy white stuff that we put in coffee or use for baking

This table sugar is a common example of a _______________________

The chemical name for table sugar is ___________________

_____________ is composed of a __________________ molecule and a _____________ molecule

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SBI3C Unit 1: Cellular BiologyJ. Lovett

Polysaccharides

Polysaccharides are complex carbohydrates made up of ___________________ _________________ linked together

Since polysaccharides are made up of several hundred to several thousand monosaccharide monomers, we consider them to be _________________

There are two main types of polysaccharides:

1. __________________ polysaccharides which store sugar, which is then used by ____________ to get energy

2. __________________ polysaccharides which are the building materials for structures that protect organisms and give them shape

The storage polysaccharide found in animal cells is called __________________

In humans, _______________ is found mainly in our ______________ and ______________ cells

Plants store a polysaccharide called _________________

Potatoes and rice are examples of “starchy” foods

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SBI3C Unit 1: Cellular BiologyJ. Lovett

Glycogen and starch are both polymers of ____________________ which means that to form them, you would take a bunch of __________________ molecules and link them together

Another common polymer of glucose is _____________________

Cellulose is the most __________________ organic compound on Earth

Fun Fact! Worldwide, plants produce almost 100 billion tons of cellulose each year

Cellulose may be familiar to you as the main component of plant products such as ___________, _____________ and _____________

Even though glycogen, starch and cellulose are all polymers of ____________________, they have different properties because of the way the __________________ of glucose are linked together

For example, our bodies can break down _____________ and _______________, but we cannot digest ________________

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