Scientific Method/Plants and Humans

Midterm Review

What is the meaning of science and how is scientific knowledge acquired?

• Science is the studies done to answer questions about the observations we make. Scientific knowledge is gained through the process of the scientific method to conduct research and experiments

basic steps of the Scientific Method. 

Observe, research, hypothesize, text hypothesis (experiments), conclude, share results

Which three cereal crops are most widely consumed globally?

• Corn, grain, rice

What is the percentage efficiency of energy transfer from one tropic level to the next in the food chain?

10%, 10% rule

The nutritional needs of the human diet can be categorized into macronutrients and micronutrients. What are  they?

• Macronutrients - carbohydrates, proteins, lipids

• Micronutrients - vitamins and minerals

similarities and differences between cereals and pseudocereals.

• Cereals belong to the plant family poaceae/grasses

• Pseudocereals do not but they resemble the appearance of cereal grains

Which types of foods are rich in simple carbohydrates, and which are rich in complex carbohydrates?

• Simple - carrots, sugarcane, beetroot

• Complex - potatoes

distinguish between modified stems and tuberous roots and give examples of each.

• Modified stems - reserves for food high in carbohydrates (starch) and low in proteins and fat, have nodes and internodes that protect the food reserve

• Tuberous roots - modified roots that become fleshy/enlarged

Why are certain amino acids considered essential (i.e. essential amino acids) for humans and must be  obtained from dietary sources? 

Certain amino acids are considered essential because they cannot be produced naturally by the human body. They must be obtained from the food we eat.

Legumes are among the most important food crops worldwide. Which macronutrient is highly abundant in  legume seeds? Explain the biological reason for its abundance.

The macronutrient abundant in legume seeds is starch. The biological reason for this is because starch also serves as the plants source of energy to grow

Which type of plant lipids serves as a source of dietary energy for humans?

• Triacylglycerols (TAGs)

Review the notes you took while watching the video “What’s wrong with what we eat?”.

• Our diets consist of too much meat and ultra-processed foods. This has caused obesity to be a big problem. 

What are vitamins and why are they important for humans?

Essential organic compounds found in very small amounts in fruits and vegetables. They are important the fundamental functions of the body

Fat Soluble Vitamins

A,D,E,K

Water Soluble Vitamins

C,B

What are phytonutrients?

Plant derived chemicals that impact human nutrition and health

Name the three major classes of phytonutrients

Terpenoids, Phenolics, Nitrogen-containing compounds

Explain the role of phytonutrients in plants

• The roles they play very from being floral pigments and scents that attract pollinators and to protect plants from high UV radiation to protect from light stress 

specific examples of phytonutrients roles

Flavonoids = floral pigments/scents that attract pollinators and protect from light stress

Which group of phytonutrients act as plant signals in legume-rhizobia interactions?

Flavonoids

difference between nutraceuticals and phytomedicines.

• Nutraceuticals - provide long-term health benefits

• Phytomedicines - target a specific health problem that can range from anticancer, antitumor, antiviral, etc.

How has knowledge of medicinal plants been acquired throughout human history?

• Trial and error - original experiments for medicinal plants

• Religious Belief

• Doctrine of Signatures - part of plants symbolized the shape of a part of the body, it would be useful to treating the disease of the human part it closely resembled

What is the Doctrine of Signatures? Give examples of plants used in traditional medicine based on the  Doctrine of Signatures.

• Doctrine of Signatures - plants appearance reveals its medicinal use

• Grapes=respiratory tract, carrots=eyes, onions=blood cells

 importance of medicinal plants in modern healthcare.

• 80% of the world's population relies heavily on locally produced medicine through plants because pharmeceutical drugs are unavaiable or to expensive to use by ⅓ of world’s population 

• 25% of our common medicines contain at least some compounds obtained from plants 

What is allelopathy in plants? 

• Plants secreting chemicals from their roots or other tissues that prevent the germination or growth of other plants in their root zone, reduces competition with other plants

Plants serve as sources for numerous therapeutic drugs available on the market or in development. Briefly describe the processes involved in drug discovery from plants.

1. Discovery and development through lab research

2. Preclinical trials that answer basic safety questions about the compound

3. Clinical research for safety and effectiveness of compound by testing on humans

4. Government review to examine data and decide it approval

5. Post-market safety monitoring to ensure the drug is safe once given to public

What are the advantages and limitations of synthetic drugs compared to natural plant-produced chemicals? Give examples of anti-cancer drugs derived from plants.

• Synthetic drugs do not depend on long-term survival of plants, they can be patented, but chemical synthesis is difficult and cheaper to be made through plants 

• EX: complex drug to treat influenza is synthesized through shikimic acid from plants

key risks threatening endangered medicinal plants.

• Habitat destruction and overharvesting

• Knowledge of medicinal plants not passed down to next generation 

Describe the methods used to conserve medicinal plants.

• In-situ conservation - identify ecosystems that house diverse medical plants and set conservation areas

• Ex-situ conservation - cultivation of plants through seed storage and field gene banks

What does ethnobotany study?

• Study of how people of a particular culture or region makes use of native plants

California has been home to the largest number of different Native people and their cultures. Which Native community’s land is the UC Davis campus located on? 

Patwin

What are the cultural importance and medicinal uses of Ayahuasca? 

• Medicinal uses; when brewed with chacruna leaves, it contains potent hallucinogen dimethyltryptamine, enzymes from the ayahuasca vine allows DMT to be absorbed

• Cultural uses; rituals

What is bioprospecting? What are some of the issues associated with bioprospecting?

Scientific studies that search for a useful application, process or product in nature.

Issues include the overcollection of native plants which causes them to become extinct

 What is biopiracy?

• Biological resources/indigenous knowledge is unethically appropriated or commercially exploited without fair compensation

What are the controverises of the Ayahuasca and Turmeric patents, what was the most important thing about them?

• 1986, US Patent and Trademark Office issued a patent for ayahuasca vine. Patent did not recognize the use of the vine in indigenous culture and had no plan to compensate them. Process to reversing it took a long time

• 1995, turmeric patent was created, commonly found in India, patent was eventually cancelled in 1996

• A noticeably important part of these patents is the time it took for the patent to be overturned. 

 three objectives of the Convention on Biodiversity (CBD).

• Conserve biological diversity

• Sustainable use of components of biological diversity

• fair/equitable sharing of benefits arising out of the utilization of genetic resources

Compare and contrast the use of petroleum-based and plant-based raw materials in the production of  industrial chemicals. 

Petroleum is a limited resource, plant-based are not. Petroleum products take longer to biodegrade than plant-based materials.

what are the concept of a biorefinery and be able to give examples of bio-based products derived from  biorefining processes. 

• Biomass → separation technology that induces catalytic conversion → ethanol, biodiesel, starch, cellulosic fibers

What are the advantages of using plant tissue or cell cultures to produce phytochemicals?

• Year-round availability of plant material

• Absence of interfering microorganisms in the soil

• Compressed vegetative cycle where we can synthesize large amounts of phytochemicals within a two-week culture period