Final Exam Flashcards
How does wind pollination occur? What structures must the flowers have?
Wind picks up the pollen from flowers and disperses them to relative species. The flowers don’t have to have a specific structure as wind isn’t basis.
How does animal pollination occur? What must flowers have?
Occur when an animal, such as a hummingbird, bee, or butterfly, take the nectar from plants and fly away dispersing it to other plants. The flowers must have a specific structure that matches up to the structure on the animal so that it can pick up nectar (co-evolution).
What is CCD?
Colony collapse disorder which is a phenomenon in which worker bees from a beehive or colony abruptly disappear due to climate change, pollution, etc.
Why are we concerned with CCD?
Bees are important pollinators for many agricultural crops worldwide.
When does fruit and seed development occur?
After the zygote and endosperm are formed.
What makes up the pericarp?
Exocarp, mesocarp, and endocarp.
What is a pericarp?
Part of a fruit formed from the wall of a ripened ovary.
Exocarp
The outermost layer of the pericarp that forms the skin.
ex. in a orange, is the orange flesh on the outside.
Mesocarp
The thick, fleshy middle layer of the pericarp.
ex. white layer that surrounds the inside of an orange.
Endocarp
Innermost layer of the fruit which surrounds the seed or carpel (female reproductive system).
ex. in an orange, it’s the lining of each fluid filled compartment.
What is the radicle?
The embryonic root that forms in a dicot seed.
What is the epicotyl?
The embryonic shoot that forms in a dicot seed.
What is the hypocotyl?
Exists between the embryonic root and shoot and bears the seedling leaves (cotyledons).
Where do all nutrients exist in a dicot seed?
The cotyledon.
What happens to flowers in oranges that lose their petals?
The ovary begins to form fruit.
What is the difference of an exocarp of an apple?
Doesn’t exist on the outside of the fruit (skin), rather on the inside forming the darker, harder part in the middle of the apple.
What are different types of fruits?
Simple fleshy, aggregate, multiple, simple dry dehiscent, and simple dry indehiscent.
What is a simple fleshy fruit?
Those that have one flower that arose from 1 carpel or fused carpel (arose from a single ovary).
What are the types of simple fleshy fruit?
Berry, drupe, hesperidium, pome, and pepo.
What is a berry fruit? Give an example.
No hard center of the fruit and contain more than one seed.
ex. tomato and grapes.
What is a drupe fruit? Give an example.
Have a hard, stony layer covering the only seed.
ex. cherry and peach
What is a pome fruit? Give an example.
Those that have a semi-cartilaginous part surrounding the seed and a surrounding fleshy part as an accessory layer.
ex. pears and apples.
What is a pepo fruit? Give an example.
Develops a thick rind.
ex. watermelon and squash.
What is a hesperidium fruit? Give an example.
A fruit whose fleshy parts are divided into segments with the whole being surrounded by a separable skin.
ex. those in the citrus family like oranges and lemons.
Parthenocarpy
Virgin fruit where there are no seeds, thus no sexual reproduction.
What is the purpose of parthenocarpy?
To encourage pollinators to keep coming to the plant, as the fruit is still being produced, just without seeds
What is an aggregate fruit?
A fruit where a single flower develops from multiple ovaries (separate carpels)
ex. strawberries or blackberries.
What is an accessory fruit?
Some fruit in which part of the flesh isn’t derived from the ovaries, rather a tissue near the carpel.
ex. strawberries or an apple
What seeds exists on strawberries?
Many achene seeds on the surface.
What is a multiple flower?
A type of fruit that develops from the ovaries of many flowers growing in a cluster (inflorescence) or that are fused together into a larger fruit (fusion of ovaries).
ex. pineapple
What is simple dry dehiscent fruit? Examples.
A fruit where the fruit dries, opening up and releasing the seed.
ex. follicle, legume, and capsule
What is a legume simple dry dehiscent?
Splits into two lines of dehiscent when maturing and drying.
What is a capsule?
Composed of more than one carpel that splits lengthwise in several sections, but a lot of effort is needed to break the hard cover.
ex. poppy plants
What is a follicle?
Formed from one carpel, but only opens up on one side.
ex. milkweed
What is simple dry indehiscent?
The fruit wall and seed coat are fused together, thus both released together during dispersal.
What is an achene?
Has a hard pericarp where a single seed sticks to the wall of the ovary.
ex. sunflower seeds
What is a grain?
A fruit containing a fused seed coat and fruit wall.
ex. corn
What is a samara?
A winged achene where the seed exists at the bottom near the attachment of the leaf to a tree.
ex. maple tree
What is a nut?
The same structure of an achene where the seed is stick to the wall of the ovary, but the ovary wall is tough and woody.
ex. walnuts
What are heirloom tomatoes?
Not made by huge manufacturers where there are made in low numbers of specific types.
What part of the tomato can’t be eaten?
The stem due to containing alkaloids which are toxic.
Why is an apple a 5 carpel fruit?
Due to a star endocarp.
What is grafting?
Joins parts from two or more plants so that they appear to grow as a single plant.
Why does grafting occur?
Reduce time as a seed doesn’t need to mature into a full tree instead root and shoot system is almost fully developed.
Explain the process of grafting.
- A stock, which is a ripe root already developed in the ground has it’s shoot cut off
- The scion, which is a branch from another tree (the one that is of interest) is attached to the stock
- Connected via tape and hormones so xylem and phloem of the vascular cambium (secondary ones) can match up nicely and develop (give girth and cork/bark)
Why are grapefruits deadly?
Interactions with medications as they increase the amount of drug that is absorbed in the body and stays in the blood longer.
How does the seed remain in the soil before proper conditions arise?
Dormant
What does the seed need to start developing?
Optimal conditions including water, nutrients, temperature, sunlight, etc.
What happens to a seed when it absorbs water?
The water blooms inside the seed, breaking the seed coat to allow the inner parts to grow and germinate.
Germination
The sprouting of a seed after a period of dormancy.
Explain the process of germination in a dicot seed.
- Radicle grows into a primary root
- The epicotyl begins to sprout from the seed coat becoming a shoot later one while the hypocotyl extends from it
- The hypocotyl extends allowing leaves to form above ground, when they sprout from the epicotyl (now forming cotyledons)
- More leaves develop due to photosynthesis and a secondary root develops
How does the seed receive nutrients before the cotyledons arise?
The endosperm
Explain the process of germination in a monocot seed.
- The radicle develops into a primary root
- The epicotyl is hidden underneath a sheath like structure known as a coleoptile
- The coleoptile forms the first leaf itself and others develop later on
Coleoptile
A sheath like structure in a monocot seed that facilities the emergence of the shoot through the soil (covers the epicotyl).
Why are tomatoes considered a fruit and a vegetable?
Botanically it is a fruit, but due to it not being eaten for dessert, it is a vegetable too.
What is asexual reproduction?
Reproduction by mitosis, resulting in organisms with the same genetic makeup (genotype).
What are the offspring of asexual reproduction considered?
Clones
What methods are used to asexually produce plants?
Growth of adventitious roots or shoots (naturally or from cuttings), grafting, and micropropagation.
Why would we want clones of fruits?
There isn’t variation, thus we know what to deal with in terms of fertilizers, rate of growth, water conditions, etc.
What are adventitious plant structures?
Structures that arise from areas that are not apical meristems and more often in unusual places.
How is a ginger an adventitious plant?
Contains an adventitious root where it’s grown from an underground horizontal modified stem known as a rhizome.
What is an adventitious shoot?
Buds growing off of a leaf forming multiple leaf structures.
What do adventitious roots in a strawberry develop from?
An above ground horizontal stem known as a stolon + runner as it produces multiple shoots are different locations.
What is cutting?
Taking a piece of vegetative tissue that when placed under the proper environmental conditions, it regenerates the missing parts forming a plant.
ex. stem, leaf, and root
Where do adventitious roots grow from?
Arise from vascular tissue area, specifically phloem.
What encourages growth for adventitious roots?
Adding synthetic auxins, which is a hormone that allows for bigger plants to develop.
Why don’t we want to pick ripe tomatoes?
Because when transported they will be bruised easily.
What is the solution to picking and transporting tomatoes to stores?
Picked way before ripened, so harder and thus won’t bruise during transport, then placed in ethylene (in an isolated room) to naturally encourage ripening before placed on shelves.
How did golden delicious apples arise and stay in the environment?
Arose from a mutation of the red delicious apple, then grafted from the original tree’s shoot to keep it alive.
Scion
Upper portion of the plant, which is usually the stem with buds.
Stock
The lower portion of the plant, which is the rootstock.
Why use grafting?
Repair damaged shoot or root system; reduces growing times (less than starting with a seed or seedling); produce scion-stock pairing that provides new tree with benefits from each of the two plant components (resistant to disease); and grow multiple fruits on one plant.
What are the problems with grafting?
Graft incompatibility (vascular tissues don’t line up) or the graft may result in a weak point where joined, thus having the produce a tree with less apples (heaviness could break the shoot).
What are advantages of asexual reproduction?
Original plant’s desirable characteristics can be maintained; uniformity among individuals; and opportunity for greater manipulation (micropropagation) of plant characteristics.
What are disadvantages of asexual reproduction?
Systemic infections (virus) in parent plant will be passed onto daughter plants; isolation and sanitary conditions required to maintain the pathogen-free plant material; and loss of diversity which could lead to inbreeding depression (one disease wipes out all).
What must happen to provide a pathogen-free plant material?
Heat treatment
Cross-pollination
Removing the stamens from one species and transferring that pollen to the carpel of another flower of the same species.
True breeding plant
Parents produce offspring that contain the same phenotypes as themselves, thus they are homozygous.
Monohybrid cross
Crossing two plants with only two alleles to produce a 3:1 ratio (dominant to recessive).
Principle of segregation
Pairs of genes are separated into sex cells, so that each gamete contains an allele of the original gene (each allele moving to opposite sides of the cell during anaphase).
Dihybrid cross
Crossing two plants with two traits (thus four alleles) to produce a 9:3:3:1 ratio.
Principle of independent assortment
Each pair of alleles separate independently from the other pairs (how the connect during metaphase).
Incomplete dominance
When the offspring is a mixture of the parents, thus it is unsure which parent is the dominant individual.
ex. red and white flowers mixed together give a pink flower
Complete dominance
Both parents are seen in the offspring, thus both are dominant (patches of colours).
ex. red and white flowers mixed together give an offspring that has has white and red patches.
Polygenic inheritance
Where multiple genes affect a single trait.
Epistasis
One gene is affected by one or more genes through modifications of silencing or masking, thus resulting in a different phenotype.
What are linked genes?
Genes that are found close together on the same chromosome, thus being inherited together to give a 3:1 ratio.
What determines if two genes will be linked or not?
How far apart they exist on a chromosome?
When does crossing over occur? How?
In prophase I due to synapsis where homologous chromosomes are joined together and share information through their chiasmata.
What happens if crossing over occurs?
2 recombinant chromosomes giving four varying possible sex cells.
What happens if crossing over doesn’t occur?
No recombinant chromosomes giving 2 possible sex cells.
Explain transcription.
RNA polymerase moves along the DNA template strand in a 3’ to 5’ direction to synthesize a mRNA transcript in the 5’ to 3’ direction.
Where does transcription occur?
The nucleus for eukaryotes and the cytoplasm for prokaryotes.
Explain translation.
A ribosome with two subunits attach to the mRNA transcript in the cytoplasm where it reads it in the 5’ to 3’ direction. tRNAs with anticodons that are complementary to the codons in the transcript (written in the opposite direction), attach to sites in the ribosome (P, A, and E) where the amino acids attached at the 3’ end of the tRNA form a polypeptide chain that becomes a protein.
Primary structure of proteins
Linear sequence of amino acids in a polypeptide chain.
Secondary structure of proteins
H bonds form between interaction within the polypeptide backbone forming alpha helices and beta pleated sheets.
Tertiary structure of proteins
The R groups of amino acids interact to fold, producing a 3D shape.
Quaternary structure of proteins
Multiple subunits interact to form a 3D shape
What is a perennial crop?
Crops that don’t need to be replanted each year, thus after harvest, they automatically grow back.
What are the advantages of a perennial crop?
Less damage done to the soil, since don’t have to do any tillage as the seeds reproduce each time without being planted.
What are the disadvantages of a perennial crop?
Since the soil is barely touched, this increases the risk of weeds and pest, thus more pesticides are used annually.
What is a polyculture of perennial crops?
Multiple crops of different species that are grown together due to the interactions with one another either during the breeding season or off season.
ex. squash, beans, and corn
What are seed banks?
A place where seeds are stored to preserve genetic diversity for the future
What is the importance of seed banks?
If the plants die out due to inbreeding depression, the preserved seeds allow the dead plants to become seedlings again and grow into monocultures, thus protecting germ plasm.
Germ plasm
The genetic material of germ cells
What is a concern for crop production if using clones?
Variation in crop growth and development (using clones, so want little to none); maintenance of future crop seed supply; and soil health and pesticide virulence (all the same so one pest would wipe out the whole crop).
What does the Germplasm Treaty deal with (3 points)?
- Cataloguing plant genetic resources and assessing threats.
- Encouraging seed (a vegetative material) for storage in seed banks; important as if not stored properly wipes out the possibility of offspring (many in tropical areas that experience destruction).
- Setting conditions for access to protected plant germplasm by sharing profits with the 1st world country that provides resources to keep the species growing and the 3rd world country that provides the workers and location of the seed banks.
How are heirloom species conserved?
Incentives are given to smaller farmer to grow these crops.
What is caffeine?
An alkaloid, which is a type of a secondary metabolite that is synthesized by the plant.
What are primary metabolites? Give examples.
Synthesized by the plant and critical for survival.
ex. carbohydrates (glucose), lipids, and proteins
How do secondary and primary metabolites differ?
Both are synthesized by the plant, but the primary ones are needed for survival while secondary can aid in growth, survival, and reproduction but not necessary.
What is the purpose of caffeine in plants?
Give plants a bitter taste, so that herbivores refuse to eat it.
What are other examples of secondary metabolites beside caffeine?
Toxins that give protection from herbivores or aromas that attract pollinators.
What are the advantages of drinking coffee?
Stops tiredness by stimulating the CNS; has antioxidants; improves athletic performance; enhances pain-relieving effects of aspirin and acetaminophen; an appetite suppressor; and increased protection against Parkinson’s, type 2 diabetes, or cancers (future research).
What are the disadvantgaes of drinking coffee?
Increases nervousness, irritability, and heart (stimulates CNS); cause insomnia due to stimulation; addictive; and increased birth defects/decreased fetal growth.
What part of a plant is a coffee bean?
Seed
What species do most caffeine products come from?
Coffea arabica
Is a coffee tree dicot or monocot? Why?
Dicot due to net veined leaves.
What are the fruit in coffee trees known as?
Cherry
How do mature fruit in a coffee tree look?
Bright red clusters like appear similar to grapes.
What is the makeup of a fruit in a coffee tree?
Pulpy covering with 2 seeds on the inside.
Where did coffee originate from?
Ethiopia
Where do we get most of our coffee now?
Brazil
What is the climate coffee grows in? Why?
Tropical climates as they are intolerant to frost.
Why doesn’t Ceylon (Sri Lanka) grow coffee trees anymore? What do they grow instead?
Their coffee trees experienced a fungal infection. Now they grow plants that are used in teas.
Explain the processing of coffee beans.
- Seedlings are planted in tropical climates
- It takes 3-5 years for the seedlings to mature (green to red)
- Fruits are picked by hand when they are ripe (red)
- Placed in baskets where they are dried (constant movement to avoid build up of microorganisms)
- Depulped once dry enough, where it loses its red coverings and the seeds are exposed
- Seeds have a dark parchment as a seed coat
- Loses the parchment so now green beans (light brown seeds)
- Roasted to produce oils that caramelize the seeds to give them a shiny, dark brown colour
How are beans decaffeinated?
Beans have caffeine removed either through wet or dry methods (still a small % of caffeine remains).
How are beans roasted?
For certain temperatures for a certain amount of time until they reach an optimal temperature for the particular type of bean they want to produce.
What is the difference between dark and light roast?
Dark roast has a more bitter taste due to being roasted at longer times and higher temperatures. Light roast has a sugary taste and contain more caffeine due to being roasted at lower temperatures.
Why are transported beans stored as green beans when leaving their tropical climates?
Because once roasted, they only last a certain period of time.
Fair trade
Employees being paid fairly
Organically grown
Good for the environment
Shade grown
Better for the environment, but more expensive.
What is an infusion?
The liquid produced from steeping (soaking) plant organ in boiling water.
What are most teas made from?
Leaves
What are most herbal teas made from?
Other parts of the plants that aren’t the leaves.
What species do non-herbal tea plants come from?
Camellia sinensis plant (all the same species)
What kind of plant is the camellia sinensis plant? Why?
Dicot due to net veined leaves.
How are tea leaves picked?
Manually
What leaves do we want for our tea?
Young leaves as they provide better flavour.
How to get different kinds of teas from the camellia sinensis plant?
The leaves are processed and fermented differently depending on what tea is the ouctome.
What non-herbal tea requires the most processing?
Black tea.
What leaves are white tea made from?
The young leaves from the trees; however, these ones are dried out to give them a white colour rather than green.
What are true teas?
Non-herbal teas
What are the differences between true teas?
Difference in flavour
How does the difference in flavour arise?
Due to flavonoids (antioxidants) and tannins (2 types of phenolics) and processing
How much caffeine do non herbal teas contain?
About 4%
What are the the four steps in processing non-herbal teas?
Withering, rolling, oxidation, and drying or firing.
Explain withering.
Newly picked leaves are dried with heated air so that the leaves become flexible.
Explain rolling.
Leaves are twisted and rolled, thus breaking cells and releasing oils. This is done by a hand or machine.
What do the oils release in rolling?
A distinctive aroma.
Explain oxidation/fermentation.
Chemical process where the oxygen is absorbed from the leaf so that it changes to a bright copper colour.
What is a differentiating process in tea processing?
Oxidation, which varies between green, oolong, and black tea.
How does oxidation differ between white/green, oolong, and black tea?
White/green = no fermentation
Oolong = semi-fermentation
Black = full fermentation
Explain drying or firing.
Leaves are dried evenly without burning, then firing stops the oxidation process.
