Biology Exam 2 Content Review

Question 1

What are characteristics that all plants share?

Answer 1

All plants have some form of chlorophyll or beta carotene, store starch as an energy products, have chloroplasts, and a flexible cell membrane.

Question 2

What cell structure do all land plants have?

Answer 2

All land plants have a cellulose cell wall outside of the flexible cell membrane for greater protection and structural support.

Question 3

How did plants evolve?

Answer 3

Plants evolved from the water to live on land.

Question 4

What contributed to the evolution of plants on land?

Answer 4

Plants started off as completely aquatic. However, there were a lot of limitations associated with living underwater. There was the limited amount of sunlight/wavelengths that could reach plants, because water absorbed a lot of the light energy. Natural selection favored plants that were living more closely to the surface of the water because those plants could get more sunlight than the plants that were further underwater. Plants need CO2 to perform photosynthesis, but CO2 is far less available underwater than it is in the air. It takes a lot of time for CO2 to diffuse down to the plants underwater. Thus, again, natural selection favors plants that live closer to the surface of the water because they don’t have to wait as long for CO2 to diffuse down to them (compared to the plants that live in deeper waters). Lastly, at the time that plants were evolving to live on land, there weren’t any major heterotrophs to consume those plants before they got the chance to develop.

Question 5

Why couldn’t plants just move onto land without any major adaptations?

Answer 5

Plants need water to grow and survive. Before the land, plants were surrounded by water all the time, so there wasn’t much need to develop complex water (and sugar) transportation systems. The water also allowed the plants to remain buoyant and reach as much sunlight as was possible in underwater conditions. However, on land, there was nothing supporting the plants to keep them upright. And without structural support, the plants wouldn’t be able to reach and obtain adequate amounts of sunlight to perform photosynthesis. Plants also used the water for sexual reproduction where the sperm would swim to the egg to fertilize it. But again, the drier environment would force the plants to develip new ways of reproducing.

Question 6

List the 5 Major Plant Phyla in Order of their Evolution

Answer 6

Chlorophyta, Bryophyta, Pteridophyta, Coniferophyta, and Anthophyta

Question 7

List the taxonomic hierarchy in order from most to least exclusive.

Answer 7

Domain, Kingdom, Phylum, Class, Order, Family, Genus, Species.

Question 8

What is the closest known ancestor to green land plants?

Answer 8

Chlorophyta

Question 9

What were the oldest vascular land plants?

Answer 9

Ferns/Pteridophyta

Question 10

How were Bryophyta able to survive on land without any vascular tissue?

Answer 10

The Bryophyta had cuticles that worked to prevent dehydration. They had stoma and lived in damp areas which allowed easier diffusion of water and nutrients, and used water to reproduce. So although they were able to survive on land, they weren’t really able to grow very tall because they didn’t have any vascular tissue.

Question 11

What is vascular tissue?

Answer 11

Vascular Tissue are used to transport water and sugar/nutrients around the plant.

Question 12

What are the first land plants?

Answer 12

Mosses are the first land plans but they aren’t the ancestors of higher/more complex land plants.

Question 13

What is the limitation of Pteridophyta?

Answer 13

Pteridophyta are the first vascular land plants, allowing them to grow taller and reach more sunlight. However, they are limited because they must still sexually reproduce in moist environments. It wasn’t until the development of the gymnosperms that plants were able to reproduce outside of water.

Question 14

What was the significance of gymnosperms in the evolution of plants onto land?

Answer 14

Gymnosperms were vascular, naked-seed plants. They were the first land plants that could reproduce without water/moist environments because of the innovation of the seed and pollen. The development of the seed helped to protect embryo against water loss & herbivory, permits dormancy, and prompted easier/vaster dispersal. The development of pollen (gametophyte) allowed plants to reproduce in dry conditions. Additionally, the Coniferophyta had cones (small ones for male and large ones for females) to protect female eggs.

Question 15

What was the significance of angiosperms?

Answer 15

Angiosperms were plants with fruit-covered seeds and flowers. The fruit increased the protection of the embryo and the flowers helped better facilitate pollination by attracting animal pollinators (although there was a lot of wind and water pollination as well). Angiosperms include Anthophyta which are the most widely distributed group of all land plants. Additionally, most angiosperms plants are annuals and herbaceous.

Question 16

What are the divisions of Anthophyta?

Answer 16

Anthophyta are separated into monocots and dicots.

Question 17

Annuals vs. herbaceous

Answer 17

Annuals - the plant dies off at the end of the year and leaves only the seeds for the next growing season.

Herbaceous - the plant is short-lived and non-woody

Question 18

What is a monocot?

Answer 18

A type of angiosperm that produces 1 leaf at germination, has scattered vascular bundles, parallel leaf veins, and flower petals in multiples of 3.

Question 19

What are dicots?

Answer 19

Dicots are angiosperms that have 2 leaves at germination, a circular arrangement of vascular bundles, branching leaf veins, and petals in multiples of 4 or 5.

Question 20

What are the small membrane layers in the chloroplasts called? And what is their significance?

Answer 20

The Thylakoid are stacked and flattened vesicles in the chloroplasts that help facilitate photosynthesis. There’s small spaces between the thylakoids that allow them to maximize surface area and contribute to more efficient extraction of radiant energy.

Question 21

Why are roots important?

Answer 21

Roots provide moisture and inorganic nutrients to the plant. They help attach the plant to the ground and support it as it grows vertically to reach more sunlight. Tuber roots (like carrots and sweet potatoes) store starch for the plant. And the snorkel roots give more access to oxygen.

Question 22

What is the tap root system?

Answer 22

Tap roots have a long central shaft to store nutrients. They reach deeper into the soil to reach deeper water tables. They are limited by shallow soils, which could hinder their ability to grow and access water. Dandelions are examples of tap roots. (They are hard to get rid of because the roots extend very far into the soil, so unless you dig out the root completely, the dandelions will continue to grow).

Question 23

What is the Fibrous/Diffuse Root System?

Answer 23

Has shorter roots that fan out into a mesh-like structure. Their primary function is to support the plant and allow access to a more shallow water supply

Question 24

What are tuber roots?

Answer 24

Tubers (like sweet potatoes) are swollen masses that store energy.

Question 25

What are snorkel roots?

Answer 25

aka Pneumatophores; They roots emerge below ground but rise above ground to obtain oxygen for respiration in the root. Snorkel roots are usually present in species that have roots in water saturated soil or standing water.

Question 26

What's the difference between roots and shoots?

Answer 26

Roots grow below ground. Shoot are the above-ground part of the plant.

Question 27

What are the advantages and disadvantages of axial versus dendritic stems/trunks/shoots?

Answer 27

Axial shoots have a central column that all branches and leaves emerge from. They have the advantage of being able to withstand heavy snow, hail, and winds in harsher environments. Their disadvantage would have to be a smaller surface-area-to-volume ratio, which means they can't perform as much photosynthesis as dendritic plants. Dendritic shoots have sub-branching structure where branches emerge and there's the emergence of more branches from those branches (there's no real central column that they all attach to). Dendritic shoots have the advantage of creating a greater surface-area-to-volume ratio between leaves and allows them to obtain more sunlight and perform more photosynthesis consistently. Their disadvantage is that there can be a lot of breakage of branches due to strong winds, ice, hail, snow, and rain.

Question 28

What is the p-value in statistics?

Answer 28

The p-value is the probability that the data matches randomness.

Question 29

What are the 5 requirements of H-W equilibrium?

Answer 29

1. Random mating 2. No mutations 3. No natural selection 4. Large/infinite population size 5. No gene flow

Question 30

Explain H-W as a null hypothesis.

Answer 30

The null hypothesis states that in a given situation, randomness prevails - there is no relationship between variables in an experiment. H-W equilibrium states that allele frequencies don't change outside of the range of what randomness would predict. Thus, because H-W depends on randomness, it can be considered a null hypothesis. The alternative hypothesis to H-W would be evolution: Evolution states that allele frequencies are changing outside of what randomness would predict. Thus, in a chi-square analysis of a population to determine if the population is in H-W equilibrium, a chi-square value that is greater than (or equal to) the critical value (under the correct degrees of freedom) will mean that we reject the null or H-W. (If the chi-square analysis of the population yields a chi-square value that is less that the critical value under the correct degrees of freedom, then you fail to reject the null/H-W and evolution is not occurring).

Question 31

What is the decision-rule for chi-square analysis?

Answer 31

IF the chi-square value is greater than or equal to the critical value, then you reject the null hypothesis. If the chi-square value is less than the critical value, then you fail to reject the nut hypothesis.

Question 32

Why is surface-area-to-volume ratio important in plant processes?

Answer 32

A greater surface-area-to-volume ratio in plants allows for greater obtention of resources like water, nutrients and sunlight. 1. The spaces between the thylakoids in the chloroplasts create a greater surface-area-to-volume ratio in the chloroplasts, allowing for more sunlight to be absorbed and more photosynthesis to take place. (The reason leaves aren't connected to each other is for this similar reason) 2. Plants' root hairs have a large surface-area-to-volume ratio which allows them to absorb/take-up greater amounts of water and nutrients.

Question 33

How do micelles function in soil to affect nutrient availability and uptake in plants?

Answer 33

Micelles are hardened mixed masses of clay and soil. They are positively charged on the inside, but are negatively charged on the outside. The outside negative charge attracts positively charged ions of nutrients like sodium, potassium, and magnesium. But these are also nutrients that plants need to live and grow. So the micelles are causing a decrease in the availability of nutrients that the plant can use.

Question 34

How do acids in soil affect nutrient uptake in plants?

Answer 34

In very fine, caly soils, acids have positively charged H+ ions and these H+ ions have a greater affinity for the negatively charged micelles than the other positively charged nutrients. So the addition of acids to the soil increases the H+ ions. And the H+ ions attract to the micelles and take up all the available attachment sites, leaving the other positively charged nutrients free to be taken up by the plants. In tropical soils, microbes' rapid decomposition generates, in effect, acids. These acids lower the soil pH, and lower soil pH as well as very frequent, and heavy precipitation, causes the leaching away of nutrients - it decreases the availability of nutrients in the soil and decreases nutrient uptake in plants. In very sandy soils, with or without lower pH, leaching away can occur because of how easily water passes through.

Question 35

What are the 5 taxonomic kindgoms?

Answer 35

1. Monera 2. Protista 3. Plantae, 4. Fungi 5. Animalia

Question 36

What are the 3 Domains?

Answer 36

1. Bacteria 2. Archaea 3. Eukarya

Question 37

What is a species?

Answer 37

A species is an evolutionarily independent group, meaning that mutation, natural selection, gene flow, genetic drift, and evolution of one group is independent of other group.

Question 38

Biological Species Concept

Answer 38

The biological species concept states that individuals that are reproductively isolated, or do not have the capacity to mate and successfully interbreed and produce fertile, viable offspring, are different species. If the two individuals can interbreed and produce viable and fertile offspring, then they are the same species. There are 2 mechanisms: 1. Prezygotic Isolation: temporal, habitat, behavioral, gametic barrier, and mechanical. 2. Postzygotic isolation: hybrid viability, hybrid sterility

Question 39

What is the limitation of the biological species concept?

Answer 39

The biological species concept is problematic for distinguishing species in the fossil record and for organisms whose populations don't overlap

Question 40

Morphospecies Concept

Answer 40

States that differences between morphological traits/features and differences in behaviors indicate that two individuals are of different species. This works for both sexual, asexual and fossilized/extinct species.

Question 41

What is the limitation of the morphospecies concept?

Answer 41

There's a problem with looking only for physical similarities between individuals because those differences seen could be formed of variation within the species -- they could be the effects of genetic drift, mutations, or natural selection. Thus, 2 organisms that look different (maybe one has a different color pattern) might be incorrectly classified as different species when they're actually the same species - one of them just happens to have a trait variation.

Question 42

Phylogenetic Species Concept

Answer 42

Takes into account a variety of traits specific to the population in order to establish relatedness and distinction between groups.

Question 43

Phylogenetic Tree

Answer 43

A phylogenetic tree is a branching diagram that depicts relatedness/distinction among groups

Question 44

What is the difference between phenetics and cladistics?

Answer 44

Phonetics is the phylogenetic grouping of species based on similarity of traits, whether those traits are ancestral or more recently derived. It treats all traits equally. On the other hand, cladistics is the grouping of species by shared, recently derived characters only. Cladistics takes into account the idea that the most likely explanation or pattern is the one that implies the least amount of change.

Question 45

What is the difference between a monophyletic grouping and a paraphyletic grouping?

Answer 45

A monophyletic grouping includes a common ancestor and ALL of its descendants. A paraphyletic grouping includes a common ancestor, but only SOME of its descendants.

Question 46

How are new species created?

Answer 46

The creation of a new species from old species is based on the isolation of one or more groups from an ancestral group, and the genetic divergence between the new and ancestral groups.

Question 47

What is the relationship between genetic diversity and the stability of a community?

Answer 47

The stability of a community is based on greater genetic diversity. More genetic variation will mean that if a huge environmental change/pressure occurs, it would be more likely for the population to survive because there are some members of the species that have a trait (caused by genetic variation) that enables them to adapt and survive in the new environment. If there isn't a lot of genetic variation, then its less likely for the population to survive: If there is no variation for one type of trait (maybe height for example), and an environmental change causes the natural selection of individuals with a certain height, but everyone in the population is the same height, then the population's stability is in danger. And because each level of the biological hierarchy affects the next, it follows that any changes at the population level will reflect on the community level (an so on). So a decrease in population stability, will cause a decrease in community stability because the community is at risk of losing an important population.

Question 48

What is the difference between allopatric and sympatric speciation?

Answer 48

Allopatric speciation is the isolation of individuals of a population due to a physical barrier. If the two sub-populations are isolated long enough, then over time they will diverge from each other and remain reproductively isolated, and develop different morphological traits that cause them to become two different species. There are 2 ways allopatric speciation can take place: 1. Vicariance - This is when the population is divided by a change in the geological landscape. If the populations are separated long enough, allele frequencies of the sub-populations will change so much that they can no longer be considered the same species. 2. Dispersal - This is when a group of individuals form the population emigrate and physically separate themselves from the rest of the original population and are isolated long enough to have allele changes that lead to the development of a new species. This is different from sympatric speciation, which is the creation of a new species where there is no physical barrier between subpopulations. Sympatric speciation often occurs due to preferences in behavior, food, reproduction, etc. For example, apple maggot flies like to lay their eggs where they were born. Apple maggot flies that were born in Hawthorne trees like to return to Hawthorne trees to lay their eggs and produce more offspring. Apple maggot flies that lay their eggs in apple trees return to apple trees to lay their eggs on apples to produce more offspring. This difference will eventually separate the populations: The Hawthorne flies will eventually only interact with other Hawthorne flies and the Apple flies will only interact with apple flies. The lack of interaction between the two sub-populations will eliminate gene flow between the 2 populations and lead to speciation.

Question 49

What is the relationship between allele frequencies, evolution, and H-W equilibrium?

Answer 49

H-W equilibrium states that allele frequencies don't change outside of what randomness would predict between one generation and the next. It implies/states that since there is no change in alleles, there's no changes in the traits that are being produced, and thus no evolution is occurring on the population. However, if there's changes in the allele frequencies from one generation to the next, then there must be some sort of force, occurrence, or natural selection taking place on the population that's causing those allele frequencies to change. And since natural selection is acting on the population, it's safe to assume that the population will begin to develop new traits and evolve. Thus, change in allele frequencies directly correspond to evolution occurring.

Question 50

How does gene flow affect speciation?

Answer 50

If two sub-populations of a species are still undergoing gene flow, then speciation will not occur because there's no true isolation of the sub-population groups. For speciation to occur, there needs to be complete genetic isolation from each other, so gene flow eliminates that possibility. (It's more likely for gene flow to affect sympatric speciation than allopatric speciation, because even if there are some preferences between one group of a population compared to another, there's no physical barrier that's preventing them from interacting - thus they won't be able to become genetically distinct from each other).

Question 51

What is the reinforcement of species ?

Answer 51

The reinforcement of species occurs when two isolated sub-population groups come back into contact with each other, and are able to interact with each other. gene flow is occuring between them which dilutes any genetic differences that were caused by the isolation. And thus, the dilution of genetic differences causes the dilution of the speciation. The reinforcement of species occurs when two isolated sub-population groups come back into contact and can interbreed and produce young hybrid offspring that have suppressed fitness.

Question 52

What are hybrid zones?

Answer 52

Hybrid zones are areas where 2 population may overlap and hybrid species exist.

Question 53

What is hybridization?

Answer 53

Hybridization is the creation of a new species of hybrids where the traits in hybrids created a difference in survival and reproduction of the hybrids relative to the non-hybrid members of the population, are selected for in the environment, and inherited by their offspring, causing evolution and the development of a new hybrid species.

Question 54

True or false: Angiosperms and gymnosperms are both vascular, seeded plants.

Answer 54

True

Question 55

How come genetic drift doesn't violate H-W equilibrium?

Answer 55

Genetic drift is the change in allele frequencies due to randomness. In other words, it changes allele frequencies but within what randomness what predict, and H-W requires that allele frequencies change only within what randomness would predict. Thus it doesn't violate H-W equilibrium.

Question 56

Why is the shoot system important?

Answer 56

The shoot system facilitates the transport of water and nutrients between the leaves and the roots of the plant. It provides access to available light above surrounding structures and allows more photosynthesis to occur. The shoot system also provides water storage (for example cacti and certain vines) and protection (like thorns/modified stems). It also provides food storage in underground stems (like tams) and allows for asexual reproduction to occur.

Question 57

Describe the 4 general leaf designs.

Answer 57

1. Simple leaf - had an Hillary bud; 1 leaf budding for a twig 2. Compound leaf - has multiple leaflets attached to a twig 3. Double Compound leaf - has leaflets on leaflets; increases the lateral leaf reach with minimal increase in leaf mass 4. Needles - gives maximum water conservation; reduced but year-round photosynthesis

Question 58

How do you know where a leaf starts and ends, or whether a leaf is simple or compound?

Answer 58

Leaves always emerge from axillary buds, or small little bumps where the leaf emerges. If there's no axillary bud, then the leaf might consists of several leaflets and thus be a compound leaf.

Question 59

Why are leaves important?

Answer 59

Leaves perform photosynthesis, collect water, store water (aloe vera, succulent plants) obtain supplementary nitrogen (carnivorous plants), defend the plant against herbivory (cactus spines) and attach to the vegetation for climbing

Question 60

What items are included in plant cells?

Answer 60

Thin cell membrane; primary cell wall (made of cellulose); secondary cell wall (inside the primary cell wall). The order of coverings is: cell membrane secondary cell wall and an outer primary cell wall.

Question 61

What defines the secondary cell wall?

Answer 61

The secondary wall is defined by specialized chemical components corresponding with the cells's specialized function. The secondary wall produced waxy substances for the cuticle and lignin for maximum strength in the xylem tissue.

Question 62

What are the least specialized plant cells and their function?

Answer 62

The Meristematic Cells are the least specialized plants cells. They're almost like the "stem cells" of animal cells. they are undifferentiated, and rapidly-dividing with only a simple primary cell wall that allows the cells to be elongated. It encompasses the layers of active plant growth (apical meristems and lateral meristems). Once cell might remain undifferentiated but others might become differentiated.

Question 63

What are parenchyma cells?

Answer 63

The Parenchyma cells are the most common mature plant cells in nature and are close descendants of meristematic cells. They only have a primary cell wall and are less actively dividing, but they have the ability to revert back to meristematic tissue, or form dermal tissue or ground tissue (so long as they haven't reached their final form). These cells remain alive and make up the phloem cells (sieve-tube cells + companion cells).

Question 64

What is the function of the Collenchyma cells?

Answer 64

The collenchyma cells are much less abundant in nature and are made up of thicker primary cell walls (more cellulose), but no secondary cells walls. The collenchyma cells support the xylem and phloem in what's known as the vascular bundle. (They can also stretch and elongate like the meristematic cells.

Question 65

What is the purpose of the Sclerenchyma cells?

Answer 65

These cells are fully differentiated and have an extra secondary cell wall made of lignin. These cells don't allowed stretching and elongation and are found in non-growth areas of the tree. They typically lose their cytoplasm and die when mature which leaves the cell wall material that forms the xylem of the plant.

Question 66

What is in the epidermal layer of leaves?

Answer 66

The Epidermis consists of the waxy cuticle that prevents water loss and protects against pathogens and herbivores. It has Trichomes which are little structures that fight against herbivores by releasing unsavory chemicals. (trichomes also work to reflect excess solar radiation and converse water in the plant). The stomata (guard cells + pores) are also located in the epidermis.

Question 67

What is the palisade mesophyll?

Answer 67

It's elongated parenchyma cells; it's the site of most photosynthesis

Question 68

What is the vascular bundle?

Answer 68

The Vascular Bundle consists of the phloem, xylem, and the supportive collenchyma cells. It's located in the mesophyll. (water renters, and carb exists)

Question 69

What is the spongy mesophyll?

Answer 69

It's beneath the palisade mesophyll and is a space for gas and water exchange; photosynthesis can also take place here but it isn't as frequent as tin the palisade mesophyll.

Question 70

What is bark made of?

Answer 70

Bark is made of cork cells.

Question 71

What are secondary phloem cells?

Answer 71

They are phlegm cells that transport the products of photosynthesis through the plant

Question 72

What is the cork cambium?

Answer 72

The cork cambium is situated between the cork (outside of the plant) and the phloem. On one side, it produces cork towards the outside of the plant, and on the otehr side, it takes up dead phloem cells, and recycles them to produce more cork.

Question 73

What are secondary xylem cells?

Answer 73

they are active in water transport

Question 74

What is sapwood?

Answer 74

Sapwood is the lightly colored xylem layer that is active in water transport.

Question 75

What is the importance of heartwood in the tree?

Answer 75

Heartwood is darkly-colored xylem in the core of a tree that no longer transports water. The heartwood is darkly colored because its stores are concentrations of anti-bodies and metals that it can't use. The storage of these impurities causes the heartwood to harden and provide a tougher structure to the tree.

Question 76

Explain the structures that are located in the roots of plants

Answer 76

There is an epidermis with lateral roots and root hairs that increase the surface area for water nutrient absorption. There's cortex cells, and parenchyma cells that store food in the ground tissue of the root. And theres the Vascular Cylinder which consists of the endodermis (has the Casparian strip), the pericle (where lateral roots begin to grow from), and the primary phloem and the primary xylem.

Question 77

What is the difference between primary and secondary plant growth?

Answer 77

Primary growth is caused by the apical meristem which increases the length of the roots and shoots. Secondary growth is casted by the lateral meristems (aka cambium) and increased the diameter of the plant.

Question 78

Why is the root cap important?

Answer 78

The root cap (loose epidermal cells) is located on the outside of the apical meristem and protects the meristem from being damaged if it grows into clay or hard soil. The root cap also secretes a lubricant called mucigel to facilitate growth through the soil.

Question 79

What is a lateral meristem?

Answer 79

The Lateral Meristem is a cylinder of actively dividing tissue tuning the length of the plant and occurring just inside the perimeter of the stem or trunk.

Question 80

What is the cork cambium?

Answer 80

The cork cambium is one type of lateral meristem that is located outside of the secondary phloem cells and produces cork (bark). It only produces cells to the outside of the cork cambium later and doesn't generate any tissue towards the inside

Question 81

What is the vascular cambium?

Answer 81

The vascular cambium is another type of lateral meristem that is located inside the cork cambium later and produces phloem cells to the outside of the cambium later and produces xylem cells inside the vascular cambium.

Question 82

How does the vascular cambium contribute to diameter growth in plants?

Answer 82

The vascular cambium produces xylem cells towards the inside of the plant. Because the xylem doesn't just disappear, this means that the cambium is constantly producing cells that start to push it farther and farther away from the center of the tree. This causes an increase in the tree's diameter.

Question 83

What is the primary design and function of flowers?

Answer 83

Flowers are designed to attract pollinators and produces seeds to protect gamers and provide for sexual reproduction.

Question 84

What's the definition of a conventional flower?

Answer 84

A conventional flower attracts pollinators, launches pollen and protect ova.

Question 85

What are sepals?

Answer 85

They are the thicker, leaf-like photosynthesizing structures that enclose the developing flower bud and other reproductive structures to protect them from insects and disease.

Question 86

What are petals?

Answer 86

Petals are thinner, leafy and colorful scented structures that attract pollinators. There's a nectary at the base of the petals that provides nectar for pollinators. (Corolla = petal assemblage)

Question 87

Stamen

Answer 87

The structure producing the male gametophyte and is composed of a filament (support shaft) and an anther (pad of pollen).

Question 88

What is the Carpel?

Answer 88

The Carpel is the reproductive structure that produces female gametophyte and is composed of an ovary with an ova, a style and a stigma (where the pollen lands and can travel down to the egg to fertilize it).

Question 89

Seed

Answer 89

Consists of the plants embryo, uses an endosperm as a nutrient source and has a seed coat (similar to the yolk and shell of a bird egg).

Question 90

Fruit

Answer 90

The fruit develops from the ovary of the plant as the seed develops. The fruit works to protect the seed from damage and may aid in dispersal by attracting predators to eat the fruit and carry the seeds elsewhere.