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1. Introduction to Anatomy & Physiology5h 43m
2. Cell Chemistry & Cell Components12h 36m
3. Energy & Cell Processes10h 6m
4. Tissues & Histology10h 3m
5. Integumentary System2h 20m
6. Bones & Skeletal Tissue2h 16m
7. The Skeletal System2h 35m
8. Joints2h 17m
9. Muscle Tissue2h 33m
10. Muscles1h 11m
11. Nervous Tissue and Nervous System1h 35m
12. The Central Nervous System1h 6m
- Introduction to the Central Nervous System
  18m
- The Cerebrum
  48m
13. The Peripheral Nervous System1h 26m
14. The Autonomic Nervous System1h 38m
15. The Special Senses2h 41m
16. The Endocrine System2h 48m
17. The Blood3h 22m
18. The Heart2h 42m
19. The Blood Vessels3h 35m
20. The Lymphatic System3h 16m
21. The Immune System14h 37m
22. The Respiratory System3h 20m
23. The Digestive System2h 5m
24. Metabolism and Nutrition4h 0m
25. The Urinary System2h 39m
26. Fluid and Electrolyte Balance, Acid Base Balance37m
27. The Reproductive System2h 5m
28. Human Development1h 21m
29. Heredity3h 32m

2. Cell Chemistry & Cell Components

Functional Groups

2. Cell Chemistry & Cell Components

Functional Groups: Videos & Practice Problems

Video Lessons Practice Worksheet

Topic summary

Functional groups are specific groups of atoms that confer reactivity to biomolecules, typically extending from a carbon backbone. Key functional groups include the methyl, hydroxyl, carbonyl, carboxyl, amino, phosphate, and sulfhydryl groups. Each plays a vital role in the structure and function of biomolecules, such as lipids and carbohydrates. Understanding these groups is essential for recognizing their significance in biological processes and molecular interactions, aiding in the comprehension of complex biochemical pathways.

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Functional Groups

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Functional Groups Video Summary

Functional groups are specific groups of atoms within molecules that are responsible for the chemical reactions of those molecules. They are commonly found in biomolecules and extend off the carbon backbone, which is often represented by squiggly lines in structural formulas. Understanding these functional groups is essential as they play a crucial role in the structure and function of various biological molecules.

In biology, there are seven primary functional groups that are important to know:

The methyl group consists of a carbon atom bonded to three hydrogen atoms (–CH₃). This group is commonly found in lipids and plays a significant role in the structure of many organic compounds.

The hydroxyl group is characterized by an oxygen atom bonded to a hydrogen atom (–OH). This group is prevalent in alcohols and carbohydrates, influencing the solubility and reactivity of molecules.

The carbonyl group features a carbon atom double-bonded to an oxygen atom (C=O). This group is found in aldehydes and ketones, affecting the properties and reactivity of sugars and other biomolecules.

The carboxyl group combines the characteristics of both the carbonyl and hydroxyl groups, consisting of a carbon atom double-bonded to an oxygen atom and also bonded to a hydroxyl group (–COOH). This functional group is essential in amino acids and fatty acids, contributing to their acidic properties.

The amino group contains a nitrogen atom bonded to two hydrogen atoms (–NH₂). This group is fundamental in amino acids, which are the building blocks of proteins, and plays a key role in the formation of peptide bonds.

The phosphate group is identified by the presence of a phosphorus atom bonded to four oxygen atoms (–PO₄^3–). This group is critical in energy transfer through ATP and is a key component of nucleic acids.

Lastly, the sulfhydryl group consists of a sulfur atom bonded to a hydrogen atom (–SH). This group is important in the structure of proteins, particularly in the formation of disulfide bonds that stabilize protein structure.

Familiarity with these functional groups will enhance your understanding of biomolecular interactions and reactions. As you progress in your studies, you may need to recognize their structures and functions, which will be vital for grasping more complex biological concepts.

example

Functional Groups Example 1

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Functional Groups Example 1 Video Summary

In this example, we analyze a molecule to identify which functional group is absent. The first functional group mentioned is the carboxyl group, which consists of a carbonyl group (C=O) and a hydroxyl group (–OH). In the given molecule, we observe a carbon double-bonded to an oxygen and a hydroxyl group attached, confirming the presence of a carboxyl group. Thus, we can eliminate this option.

Next, we identify the hydroxyl group, characterized by the –OH structure. Since this group is also present in the molecule, we can cross off this option as well.

We then look for the amino group, which contains a nitrogen atom. The presence of a nitrogen atom in the molecule indicates that the amino group is indeed present.

Finally, we consider the sulfhydryl group, which is defined by the presence of a sulfur atom bonded to a hydrogen atom (–SH). Since there are no sulfur atoms in the molecule, we conclude that the sulfhydryl group is the only one not present. Therefore, the correct answer is the sulfhydryl group.

Problem

What is the name of the functional group shown in the figure?

a) Carbonyl.
b) Ketone.
c) Carboxyl.
d) Methyl.
e) Phosphate.

Carbonyl.

Ketone.

Carboxyl.

Methyl.

Phosphate.

Problem

All of the following are examples of functional groups in biology except:
a) -CH₃.
b) -COOH.
c) -H₂O.
d) -NH₂.
e) -OH.

-CH₃

-COOH

-H₂O

-NH₂

-OH

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What are functional groups in biology?

Functional groups in biology are specific groups of atoms within molecules that are responsible for the characteristic chemical reactions of those molecules. They typically extend from a carbon backbone and include groups such as methyl, hydroxyl, carbonyl, carboxyl, amino, phosphate, and sulfhydryl. Each functional group has distinct properties and reactivity, playing crucial roles in the structure and function of biomolecules like lipids and carbohydrates. Understanding these groups is essential for recognizing their significance in biological processes and molecular interactions.

Why are functional groups important in biochemistry?

Functional groups are important in biochemistry because they determine the reactivity and properties of biomolecules. They influence how molecules interact with each other and with their environment, which is crucial for biochemical processes. For example, the hydroxyl group makes molecules more soluble in water, while the carboxyl group can act as an acid. These groups are involved in forming bonds, participating in chemical reactions, and contributing to the overall structure and function of biomolecules, making them essential for understanding biochemical pathways and mechanisms.

What is the difference between a carbonyl group and a carboxyl group?

The carbonyl group consists of a carbon atom double-bonded to an oxygen atom (C=O). It is found in aldehydes and ketones. The carboxyl group, on the other hand, is a combination of a carbonyl group and a hydroxyl group (–COOH). It consists of a carbon atom double-bonded to an oxygen atom and single-bonded to a hydroxyl group. The carboxyl group is acidic and can donate a proton (H⁺), making it important in organic acids like amino acids and fatty acids.

How do you identify a phosphate group in a molecule?

A phosphate group is identifiable by the presence of a phosphorus atom bonded to four oxygen atoms, typically represented as PO₄³⁻. It is unique among the common functional groups because it contains phosphorus. Phosphate groups are crucial in energy transfer, as seen in ATP (adenosine triphosphate), and in the formation of DNA and RNA backbones. Recognizing the phosphate group is essential for understanding its role in cellular energy and genetic material.

What role does the amino group play in biomolecules?

The amino group (–NH₂) contains a nitrogen atom bonded to two hydrogen atoms. It is a key functional group in amino acids, the building blocks of proteins. The amino group can act as a base, accepting a proton (H⁺), which is important for the structure and function of proteins. It also participates in forming peptide bonds during protein synthesis, linking amino acids together. Understanding the amino group is crucial for studying protein structure and function.