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7.2: Carbohydrates - Biology

7.2: Carbohydrates - Biology


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Learning Objectives

  • Give examples of monosaccharides and polysaccharides
  • Describe the function of monosaccharides and polysaccharides within a cell

The most abundant biomolecules on earth are carbohydrates. From a chemical viewpoint, carbohydrates are primarily a combination of carbon and water, and many of them have the empirical formula (CH2O)n, where n is the number of repeated units. This view represents these molecules simply as “hydrated” carbon atom chains in which water molecules attach to each carbon atom, leading to the term “carbohydrates.” Although all carbohydrates contain carbon, hydrogen, and oxygen, there are some that also contain nitrogen, phosphorus, and/or sulfur. Carbohydrates have myriad different functions. They are abundant in terrestrial ecosystems, many forms of which we use as food sources. These molecules are also vital parts of macromolecular structures that store and transmit genetic information (i.e., DNA and RNA). They are the basis of biological polymers that impart strength to various structural components of organisms (e.g., cellulose and chitin), and they are the primary source of energy storage in the form of starch and glycogen.

Monosaccharides: The Sweet Ones

In biochemistry, carbohydrates are often called saccharides, from the Greek sakcharon, meaning sugar, although not all the saccharides are sweet. The simplest carbohydrates are called monosaccharides, or simple sugars. They are the building blocks (monomers) for the synthesis of polymers or complex carbohydrates, as will be discussed further in this section. Monosaccharides are classified based on the number of carbons in the molecule. General categories are identified using a prefix that indicates the number of carbons and the suffix –ose, which indicates a saccharide; for example, triose (three carbons), tetrose (four carbons), pentose (five carbons), and hexose (six carbons) (Figure (PageIndex{1})). The hexose D-glucose is the most abundant monosaccharide in nature. Other very common and abundant hexose monosaccharides are galactose, used to make the disaccharide milk sugar lactose, and the fruit sugar fructose.

Monosaccharides of four or more carbon atoms are typically more stable when they adopt cyclic, or ring, structures. These ring structures result from a chemical reaction between functional groups on opposite ends of the sugar’s flexible carbon chain, namely the carbonyl group and a relatively distant hydroxyl group. Glucose, for example, forms a six-membered ring (Figure (PageIndex{2})).

Exercise (PageIndex{1})

Why do monosaccharides form ring structures?

Disaccharides

Two monosaccharide molecules may chemically bond to form a disaccharide. The name given to the covalent bond between the two monosaccharides is a glycosidic bond. Glycosidic bonds form between hydroxyl groups of the two saccharide molecules, an example of the dehydration synthesis described in the previous section of this chapter:

[ ext{monosaccharide—OH} + ext{HO—monosaccharide} ⟶ underbrace{ ext{monosaccharide—O—monosaccharide}}_{ ext{disaccharide}}]

Common disaccharides are the grain sugar maltose, made of two glucose molecules; the milk sugar lactose, made of a galactose and a glucose molecule; and the table sugar sucrose, made of a glucose and a fructose molecule (Figure (PageIndex{3})).

Polysaccharides

Polysaccharides, also called glycans, are large polymers composed of hundreds of monosaccharide monomers. Unlike mono- and disaccharides, polysaccharides are not sweet and, in general, they are not soluble in water. Like disaccharides, the monomeric units of polysaccharides are linked together by glycosidic bonds.

Polysaccharides are very diverse in their structure. Three of the most biologically important polysaccharides—starch, glycogen, and cellulose—are all composed of repetitive glucose units, although they differ in their structure (Figure (PageIndex{4})). Cellulose consists of a linear chain of glucose molecules and is a common structural component of cell walls in plants and other organisms. Glycogen and starch are branched polymers; glycogen is the primary energy-storage molecule in animals and bacteria, whereas plants primarily store energy in starch. The orientation of the glycosidic linkages in these three polymers is different as well and, as a consequence, linear and branched macromolecules have different properties.

Modified glucose molecules can be fundamental components of other structural polysaccharides. Examples of these types of structural polysaccharides are N-acetyl glucosamine (NAG) and N-acetyl muramic acid (NAM) found in bacterial cell wall peptidoglycan. Polymers of NAG form chitin, which is found in fungal cell walls and in the exoskeleton of insects.

Exercise (PageIndex{2})

What are the most biologically important polysaccharides and why are they important?

Key Concepts and Summary

  • Carbohydrates, the most abundant biomolecules on earth, are widely used by organisms for structural and energy-storage purposes.
  • Carbohydrates include individual sugar molecules (monosaccharides) as well as two or more molecules chemically linked by glycosidic bonds. Monosaccharides are classified based on the number of carbons the molecule as trioses (3 C), tetroses (4 C), pentoses (5 C), and hexoses (6 C). They are the building blocks for the synthesis of polymers or complex carbohydrates.
  • Disaccharides such as sucrose, lactose, and maltose are molecules composed of two monosaccharides linked together by a glycosidic bond.
  • Polysaccharides, or glycans, are polymers composed of hundreds of monosaccharide monomers linked together by glycosidic bonds. The energy-storage polymers starch and glycogen are examples of polysaccharides and are all composed of branched chains of glucose molecules.
  • The polysaccharide cellulose is a common structural component of the cell walls of organisms. Other structural polysaccharides, such as N-acetyl glucosamine (NAG) and N-acetyl muramic acid (NAM), incorporate modified glucose molecules and are used in the construction of peptidoglycan or chitin.

Multiple Choice

By definition, carbohydrates contain which elements?

A. carbon and hydrogen
B. carbon, hydrogen, and nitrogen
C. carbon, hydrogen, and oxygen
D. carbon and oxygen

C

Monosaccharides may link together to form polysaccharides by forming which type of bond?

A. hydrogen
B. peptide
C. ionic
D. glycosidic

D

Matching

Match each polysaccharide with its description.

___chitinA. energy storage polymer in plants
___glycogenB. structural polymer found in plants
___starchC. structural polymer found in cell walls of fungi and exoskeletons of some animals
___celluloseD. energy storage polymer found in animal cells and bacteria

C, D, A, B

Short Answer

What are monosaccharides, disaccharides, and polysaccharides?

Critical Thinking

The figure depicts the structural formulas of glucose, galactose, and fructose. (a) Circle the functional groups that classify the sugars either an aldose or a ketose, and identify each sugar as one or the other. (b) The chemical formula of these compounds is the same, although the structural formula is different. What are such compounds called?

Structural diagrams for the linear and cyclic forms of a monosaccharide are shown. (a) What is the molecular formula for this monosaccharide? (Count the C, H and O atoms in each to confirm that these two molecules have the same formula, and report this formula.) (b) Identify which hydroxyl group in the linear structure undergoes the ring-forming reaction with the carbonyl group.

The term “dextrose” is commonly used in medical settings when referring to the biologically relevant isomer of the monosaccharide glucose. Explain the logic of this alternative name.


Biological Molecules: Grade 9 Understanding for IGCSE Biology 2.7 2.8

You will have studied the Biological Molecules section in some detail I would imagine, perhaps in more detail than is absolutely required for the specification. This post is meant to help you focus your understanding onto those points that are most likely to be tested in iGCSE questions. Here goes…

You do need to understand some chemistry for this topic to make sense. In particular you need to understand what is meant by the following terms:

My personal definitions would be as follows:

Atom: the smallest particle that retains the chemical properties of the element – a structure made up of protons, neutrons and electrons

Molecule: a particle made of two or more atoms chemically bonded together – may contain just one type of atom or several

Element: a substance in which all the atoms are the same

Compound: a substance containing more than one type of element

Living organisms are made from a fairly small group of molecules. The commonest molecule in every organism is water and in humans water makes up about 70% of the mass. But if you were to remove all water, leaving behind just the dry mass, the most common molecules could be grouped into proteins, lipids, carbohydrates and nucleic acids (e.g DNA)

Carbohydrates contain just three elements – carbon, hydrogen and oxygen

Lipids (fats and oils) contain three elements – carbon, hydrogen and oxygen

Proteins contain four or five elements – carbon, hydrogen, oxygen, nitrogen and sometimes sulphur

Big idea: many of the molecules that living things are made from are examples of polymers. A polymer is a large molecule made up of a long chain of repeating subunits (called monomers)

Carbohydrates are grouped into three main types:

Simple sugars like glucose or fructose – these are called monosaccharides.

Some sugars like sucrose are made of two simple sugars joined together – these are called disaccharides

Some carbohydrates are macromolecules (polymers) made of many hundreds of sugar residues joined together – these are called polysaccharides.

You can see from the diagram above that there are three important polysaccharides in living organisms. All three are polymers of the sugar glucose but the arrangement of the glucose residues is different. Cellulose is the main constituent of plant cell walls. Starch is a storage polysaccharide found in plants and Glycogen is a similar storage molecule found in liver and muscle tissue in animals.

Glucose is detected using a Benedict’s Test. Heat the solution with Benedict’s,reagent to 90 degrees for 5 minutes. A positive test for glucose is a brick red colour.

Starch is tested for using iodine solution (in potassium iodide) Iodine solution turns blue-black in the presence of starch.

Proteins are also polymers but this time the individual monomer is not a sugar but a molecule called an amino acid.

This protein is then folded up into a complex 3D shape using a whole load of weak bonds that can easily be broken at high temperatures. This is why enzymes, made of protein, denature at high temperatures.

There are 20 different amino acids that could be incorporated into a protein so there are an almost limitless variety of different proteins that can be made.

Lipids are a group of water-repelling molecules that again contain C,H and O atoms. They used to be separated into fats and oils depending in whether they are a solid (fat) or liquid (oil) at room temperature. Many lipids are a type of molecule called a triglyceride and this is made of a single molecule of glycerol attached to three fatty acid tails.


Carbohydrates and Lipids - planning sheet 2.3

Planning sheet for carbohydrates and lipidsUnderstanding(s)Sugar Analysis Expt (new guide)Condensation & Hydrolysis Calorimetry experiment (new guide)Dietary fats and BMIEssential Question(s) TOK / Nature of Science / IMDietary fats and BMISkills students will haveActivity in Calorimetry experiment Time: 1h A powerpoint presentation for a teacher use while explaining how two glucose molecules form a dissacharide by.

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Sugars

Sugars are the general name for sweet, short-chain, soluble carbohydrates, which are found in many foods. Their function in living things is to provide energy . The simplest sugars consist of a single monosaccharide . They include glucose, fructose, and galactose. Glucose is a simple sugar that is used for energy by the cells of living things. Fructose is a simple sugar found in fruits, and galactose is a simple sugar found in milk. Their chemical structures are shown in Figure 3.4.3. All monosaccharides have the formula C6H12O6.

Figure 3.4.3 Five important monosaccharides.

Other sugars contain two monosaccharide molecules and are called disaccharides . These include sucrose (table sugar), maltose, and lactose. Sucrose is composed of one fructose molecule and one glucose molecule, maltose is composed of two glucose molecules, and lactose is composed of one glucose molecule and one galactose molecule. Lactose occurs naturally in milk. Some people are lactose intolerant because they can’t digest lactose. If they drink milk, it causes gas, cramps, and other unpleasant symptoms, unless the milk has been processed to remove the lactose.


Search Results related to carbohydrates on Search Engine

Mayoclinic.org

Carbohydrates are a type of macronutrient found in many foods and beverages. Most carbohydrates occur naturally in plant-based foods, such as grains. Food manufacturers also add carbohydrates to processed foods in the form of starch or added sugar. Common sources of naturally occurring carbohydrates include:

DA: 59 PA: 81 MOZ Rank: 9

Heart.org

Food contains three types of carbohydrates: sugar, starches and fiber. Carbohydrates are either called simple or complex, depending on the food’s chemical structure and how quickly the sugar is digested and absorbed.

DA: 88 PA: 92 MOZ Rank: 33

Harvard.edu

Carbohydrates are found in a wide array of both healthy and unhealthy foods—bread, beans, milk, popcorn, potatoes, cookies, spaghetti, soft drinks, corn, and cherry pie. They also come in a variety of forms. The most common and abundant forms are sugars, fibers, and starches. Foods high in carbohydrates are an important part of a healthy diet.

DA: 76 PA: 77 MOZ Rank: 26

Cdc.gov

1 serving = 5 grams carbohydrate Non-starchy vegetables include asparagus, beets, broccoli, carrots, cauliflower, eggplant, green beans, greens, (collard, dandelion, mustard, purslane, turnip), mushrooms, onions, pea pods, peppers, spinach, squash (summer, crookneck, zucchini), and tomatoes.

DA: 36 PA: 86 MOZ Rank: 74

Wikipedia.org

Carbohydrates are central to nutrition and are found in a wide variety of natural and processed foods. Starch is a polysaccharide. It is abundant in cereals (wheat, maize, rice), potatoes, and processed food based on cereal flour, such as bread, pizza or pasta.

DA: 36 PA: 64 MOZ Rank: 100

Byjus.com

Carbohydrates are macronutrients and are one of the three main ways by which our body obtains its energy. They are called carbohydrates as they comprise carbon, hydrogen and oxygen at their chemical level. Carbohydrates are essential nutrients which include sugars, fibers and starches.

DA: 71 PA: 34 MOZ Rank: 20

Britannica.com

Carbohydrates are formed by green plants from carbon dioxide and water during the process of photosynthesis. Carbohydrates serve as energy sources and as essential structural components in organisms in addition, part of the structure of nucleic acids, which contain genetic information, consists of carbohydrate.

DA: 11 PA: 12 MOZ Rank: 50

Livescience.com

Carbohydrates are the sugars, starches and fibers found in fruits, grains, vegetables and milk products. Though often maligned in trendy diets, carbohydrates — one of the basic food groups — are.

DA: 60 PA: 66 MOZ Rank: 63

Medicalnewstoday.com

Carbohydrates are the main source of energy for the body. They are the sugars, starches, and dietary fiber that occur in plant foods and dairy products. Carbohydrates are mainly found in plant.

DA: 33 PA: 67 MOZ Rank: 41

Healthline.com

Carbs, or carbohydrates, are molecules that have carbon, hydrogen, and oxygen atoms. In nutrition, “carbs” refers to one of the three macronutrients. The other two are protein and fat. Dietary.


Low carbohydrate versus isoenergetic balanced diets for reducing weight and cardiovascular risk: a systematic review and meta-analysis

Background: Some popular weight loss diets restricting carbohydrates (CHO) claim to be more effective, and have additional health benefits in preventing cardiovascular disease compared to balanced weight loss diets.

Methods and findings: We compared the effects of low CHO and isoenergetic balanced weight loss diets in overweight and obese adults assessed in randomised controlled trials (minimum follow-up of 12 weeks), and summarised the effects on weight, as well as cardiovascular and diabetes risk. Dietary criteria were derived from existing macronutrient recommendations. We searched Medline, EMBASE and CENTRAL (19 March 2014). Analysis was stratified by outcomes at 3-6 months and 1-2 years, and participants with diabetes were analysed separately. We evaluated dietary adherence and used GRADE to assess the quality of evidence. We calculated mean differences (MD) and performed random-effects meta-analysis. Nineteen trials were included (n = 3209) 3 had adequate allocation concealment. In non-diabetic participants, our analysis showed little or no difference in mean weight loss in the two groups at 3-6 months (MD 0.74 kg, 95%CI -1.49 to 0.01 kg I2 = 53% n = 1745, 14 trials moderate quality evidence) and 1-2 years (MD 0.48 kg, 95%CI -1.44 kg to 0.49 kg I2 = 12% n = 1025 7 trials, moderate quality evidence). Furthermore, little or no difference was detected at 3-6 months and 1-2 years for blood pressure, LDL, HDL and total cholesterol, triglycerides and fasting blood glucose (>914 participants). In diabetic participants, findings showed a similar pattern.

Conclusions: Trials show weight loss in the short-term irrespective of whether the diet is low CHO or balanced. There is probably little or no difference in weight loss and changes in cardiovascular risk factors up to two years of follow-up when overweight and obese adults, with or without type 2 diabetes, are randomised to low CHO diets and isoenergetic balanced weight loss diets.

Conflict of interest statement

Competing Interests: No authors currently receive or have received funds from commercial organizations that could directly or indirectly benefit from the question addressed by this research or its findings. PG is Director of Evidence Building and Synthesis Research Consortium that receives money to increase the number of evidence-informed decisions by intermediary organizations, including WHO and national decision makers that benefit the poor in middle and low income countries. The Centre for Evidence-based Health Care at Stellenbosch University receives a grant from the Consortium for influencing evidence-informed decisions in the sub-Saharan region, and to develop capacity of researchers to respond to requests for timely, informed systematic reviews to inform national policies. The Heart and Stroke Foundation South Africa requested this review but did not contribute in any way financially or other, to its implementation. This does not alter the authors' adherence to all the PLOS ONE policies on sharing data and materials.

Figures

Figure 1. Flow diagram illustrating the search…

Figure 1. Flow diagram illustrating the search results and selection process, as well as the…

Figure 2. Risk of bias: systematic review…

Figure 2. Risk of bias: systematic review authors' judgements about each risk of bias item…

Figure 3. Forest plot of low carbohydrate…

Figure 3. Forest plot of low carbohydrate versus balanced diets in overweight and obese adults…

Figure 4. Forest plot of low carbohydrate…

Figure 4. Forest plot of low carbohydrate versus balanced diets in overweight and obese adults…

Figure 5. Forest plot of low carbohydrate…

Figure 5. Forest plot of low carbohydrate versus balanced diets in overweight and obese adults…

Figure 6. Forest plot of low carbohydrate…

Figure 6. Forest plot of low carbohydrate versus balanced diets in overweight and obese adults…


7.2: Carbohydrates - Biology

1. In some respects, the ________________ is like a factory.

2. These structures are known as &ldquolittle organs.&rdquo ________________.

3. Cell biologists divide the eukaryotic cell into two major parts the
________________________ and the _____________________________________________.

4. See Figure 7-7. What part of the nucleus (with pointer) contains a small, dense region? ______________________________________________

5. The nucleus is surrounded by a ____________________________ composed of two membranes.

6. When a cell divides, however __________________ condenses to form __________________.

7. _________________________ are small particles of RNA and protein found throughout the cytoplasm.

8. The portion of the ___________________ involved in the synthesis of proteins is called _________________________ or ___________________________.

9. See Figure 7-9. What does the Golgi apparatus do to proteins? ___________________________

10. The Golgi apparatus is somewhat like a ___________________________, where the finishing touches are put on proteins before they are ready to leave the &ldquofactory.&rdquo

11. One function of __________________________ is the digestion, or breakdown, of lipids, carbohydrates, and proteins into ________________________________ that can be used by the rest of the cell.

12. What kind of vacuole does the paramecium in Figure 7-10 contain? ____________________________

13. Most cells get energy in one of two ways ---- from ________________________ or from the ___________.

14. ___________________________ are organelles that convert the chemical energy stored in food into compounds that are more convenient for the cell to use.

15. ______________________________ are the biological equivalents of solar power plants.

16. Unlike other organelles that contain no DNA, ________________________ and ____________________ contain their own genetic information in the form of small DNA molecules.

17. Eukaryotic cells have a structure --- the _____________________________ --- that helps support the cell.

18. ___________________________ assembly and disassembly is responsible for the cytoplasmic movements that allow cells, such amoebas, to crawl along surfaces.

19. What plays a critical role in maintaining a cell&rsquos shape? ________________________

20. _____________________ are located near the nucleus and help to organize cell division. _____________________ are not found in plant cells.

/>This work is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License.


Background

Recent studies have revealed a surprisingly large number of duplicated genes in eukaryotic genomes [1, 2]. Many of these duplicated genes seem to have been created in large-scale, or even genome-wide duplication events [3, 4]. Whole genome duplication is particularly prominent in plants and most of the angiosperms are believed to be ancient polyploids, including a large proportion of our most important crops such as wheat, maize, soybean, cabbage, oat, sugar cane, alfalfa, potato, coffee, cotton and tobacco [5–8]. For over 100 years, gene and genome duplications have been linked to the origin of evolutionary novelties, because it provides a source of genetic material on which evolution can work ([9] and references therein). In general, four possible fates are usually acknowledged for duplicated genes. The most likely fate is gene loss or nonfunctionalization [1, 10–12], while in rare cases one of the two duplicates acquires a new function (neofunctionalization) [13]. Subfunctionalization, in which both gene copies lose a complementary set of regulatory elements and thereby divide the ancestral gene's original functions, forms a third potential fate [14–17]. Finally, retention is recognized for two gene copies that, instead of diverging in function, remain largely redundant and provide the organism with increased genetic robustness against harmful mutations [18–20].

The functional divergence of duplicated genes has been extensively studied at the sequence level to investigate whether genes evolve at faster rates after duplication, or are under positive or purifying selection [21–26]. The recent availability of functional genomics data, such as expression data from whole-genome microarrays, opens up completely novel ways to investigate the divergence of duplicated genes, and several studies using such data have already provided intriguing new insights into gene fate after duplication. In yeast, for instance, Gu and co-workers [27] found a significant correlation between the rate of coding sequence evolution and divergence of expression and showed that most duplicated genes in this organism quickly diverge in their expression patterns. In addition, they showed that expression divergence increases with evolutionary time. Makova and Li [28] analyzed spatial expression patterns of human duplicates and came to the same conclusions. They calculated the proportion of gene pairs with diverged expression in different tissues, and found evidence for an approximately linear relationship with sequence divergence. Wagner [29] showed that the functional divergence of duplicated genes is often asymmetrical because one duplicate frequently shows significantly more molecular or genetic interactions/functions than the other. Adams and co-workers [30] examined the expression of 40 gene pairs duplicated by polyploidy in natural and synthetic tetraploid cotton and showed that, although many pairs contributed equally to the transcriptome, a high percentage exhibited reciprocal silencing and biased expression and were developmentally regulated. In a few cases, genes duplicated through polyploidy events were reciprocally silenced in different organs, suggesting subfunctionalization.

In Arabidopsis, Blanc and Wolfe [31] investigated the expression patterns of genes that arose through gene duplication and found that about 62% of the recent duplicates acquired divergent expression patterns, which is in agreement with previous observations in yeast and human. In addition, they identified several cases of so-called 'concerted divergence', where single members of different duplicated genes diverge in a correlated way, resulting in parallel networks that are expressed in different cell types, developmental stages or environmental conditions. Also in Arabidopsis, Haberer et al. [32] studied the divergence of genes that originated through tandem and segmental duplications by using massively parallel signature sequencing (MPSS) data and concluded that, besides a significant portion of segmentally and tandemly duplicated genes with similar expression, the expression of more than two-thirds of the duplicated genes diverged in expression. However, expression divergence and divergence time were not significantly correlated, as opposed to findings in human and yeast (see above). In a small-scale study on regulatory genes in Arabidopsis, Duarte et al. [33] performed an analysis of variance (ANOVA) and showed that 85% of the 280 paralogs exhibit a significant gene by organ interaction effect, indicative of sub- and/or neofunctionalization. Ancestral expression patterns inferred across a type II MADS box gene phylogeny indicated several cases of regulatory neofunctionalization and organ-specific nonfunctionalization.

In conclusion, recent findings demonstrate that a majority of duplicated genes acquire different expression patterns shortly after duplication. However, whether the fate of a duplicated gene also depends on its function is far less understood. The model plant Arabidopsis has a well-annotated genome and, in addition to many small-scale duplication events, there is compelling evidence for three genome duplications in its evolutionary past [34–37], hereafter referred to as 1R, 2R, and 3R. Recently, a nonrandom process of gene loss subsequent to these different polyploidy events has been postulated [12, 31, 38]. Maere et al. [12] have shown that gene decay rates following duplication differ considerably between different functional classes of genes, indicating that the fate of a duplicated gene largely depends on its function. Here, we study the expression divergence of genes that were created during both large- and small-scale gene duplication events by means of two compiled microarray datasets. The influence of the origin (mode of duplication) and the function of the duplicated genes on expression divergence are investigated.


Food Sources of Protein

While people commonly associate protein with animal foods, such as meat, poultry, seafood, eggs and dairy products, many plant foods are also rich in protein, says the USDA. These include seeds, nuts, peas and beans, including soy products like tofu.

The USDA advocates getting protein from a variety of food sources. Because fatty fish like salmon and tuna are rich in healthful omega-3 fatty acids, feature them in a meal at least twice a week. Plant protein sources are appropriate for either a side dish or the main dish.

Examples include stir-fry tofu, bean soup or hummus, a spread made with chickpeas. Unsalted nuts make a nutritious snack, but you can also add them to salads or use them to replace meat in main dishes. The National Cancer Institute warns that red and processed meats are linked to cancer, so try to limit them in your diet.


Honors Biology @ Lawrenceville

Today students built models of carbohydrates and learned how monosaccharides join together to form di and polysaccharides.

1. Which elements do carbohydrates contain, and in what ratio?

2. If a sugar compound has 11 oxygen atoms, how many hydrogen atoms does it contain?

3. Based on their molecular formulas, which of the following are NOT carbohydrates?

a. C3H803
b. C10H18O9
c. C18H32O16
d. C4H8O2
e. C16H32O2
f. C6H12O6

4. For each molecule below, determine if it is a monosaccharide, a disaccharide, or a polysaccharide. You will need to look these up on your own.

5. Describe a biological function for each of the following carbohydrates
a. Cellulose
b. Ribose
c. Starch
d. Glycogen
e. Deoxyribose
f. Fructose
g. Sucrose

6. Draw the molecular structure of the following carbohydrates:
RIBOSE
GLUCOSE

7. Briefly describe the process of the condensation reaction (dehydration synthesis) for carbohydrates.

8. Briefly describe the process of the hydrolysis reaction for carbohydrates.


Watch the video: Unit Classification of Carbohydrates (May 2022).


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