Xylem

Xylem is a transport tissue found inside vascular plants. The function of the xylem is to transport water and occasionally nutrients from the roots up to the rest of the plant. It can accomplish this either through cohesion, which is the attractive force between molecules, or transpiration, which is the evaporation of water on the surface of leaves. The celery shown above highlights the xylem while also demonstrating its function. The celery's xylem was able to transport the colored water up the stalk through cohesion. As a result, we can now see the areas in which water and nutrients are transported through a celery plant.

Stigma and Style of a Carpel

The long stalk in the middle of this hibiscus flower is called a carpel. The carpel is another female reproductive organ found in the flower. It is comprised of two main parts called the stigma and style. On the hibiscus, the stigma is the the red tip of the central stalk. This is where pollen is received from pollinators. The rest of the stalk is the style. The style connect the stigma and the ovule to each other, sending down the male gametes within the pollen to fertilize the ovule.

Population

A population is a group of organisms from the same species that live together in one area at the same time. Typically these organisms can interbreed, meaning they are able to breed together without complications. The banana trees shown in the picture are an example of a population because they are similar organisms that are able to reproduce and continue producing banana trees just like it.

Parenchyma Cells

Parenchyma cells are thin-walled cells and is what most of this leaf shown here is comprised of. These cells form a "filler" layer that is found in plant leaves, stems, and roots. These cells have mainly three functions, depending on where they are located. These functions include storage and photosynthesis. These cells contain large vacuoles that are helpful for storage purposes. They also house chloroplasts, which is where photosynthesis mainly takes place.

Exoskeleton

Most animals, like mammals, birds, and some fish, have an internal skeleton that support their bodies and organs and allow movement. Exoskeletons, on the other hand, are external structures that support and protect an animal's body. It is comprised of chitin and calcium carbonate and can be primarily found on arthropods, like the ants shown above. The ant's exoskeleton is fairly hard so that it can protect its internal organs. Mobility isn't much of a problem for organisms like the ant, despite the tough skeleton, because of its segmented body.

Modified Stem of a Plant

A modified stem is a type of specialized stem that has more functions besides transportation and support. Just like modified leaves, modified stems change themselves to help the plant survive in its environment. Some stems modify themselves overtime to have different shapes or, like the rose stem in the photo, develop protective thorns to keep predators away from it. 

Modified Leaf of a Plant

Modified leaves are plant leaves that can perform functions besides just photosynthesis and transpiration This kind of adaption allows the plant to either protect itself or make it more approachable for insects. In the case of this aloe vera, its leaves are modified to have thorns, which protect it from potential predators. Its thick leaves also allow the aloe vera the ability to store water.

Mating Behavior

Mating behavior refers to the behaviors animals demonstrate or the characteristics that animals have that are used to attract mates to reproduce with. The type of courtship depends on the specific animal. Some animals have mating calls while others put on elaborate displays. This Anole lizard in the photo above is using the display method by puffing out its throat to attract female lizards. It will also engage in a mating dance that consists of push ups and head bobbing.

Lichen

Here is an example of lichen. Lichen is a slow growing composite organism. This means that it is actually a group of different organisms that symbiotically combine to become a new and different organism. Lichen is comprised of fungus, alga, and/or cyanobacterium. It has the ability to photosynthesize but it does not have a root system to receive nutrients. However, this does not pose a problem for the lichen and the lack of roots means it can grow on rocks without threatening its livelihood. This also means it can grow on organisms like this tree and it won't become parasitic or harmful to the host.

K-Strategist

A K-strategist is a species that lives in a stable environment and spend a greater amount of time nurturing their young to ensure they are capable of surviving on their own when they are of age. For instance, the ducks seen in the photo are k-strategists because they provide extra parental care to their young offspring until they become mature ducks. Other k-strategist characteristics that these ducks possess are larger bodies, fewer offspring, and longer life expectancies, a result of the extra nurturing. Besides ducks, other examples of k-strategists are humans, primates, and elephants.

Introduced Species

The macadamia nut shown in the photo is an example of an introduced species to Hawaii. An introduced species is a foreign species that is introduced to the environment by humans, whether it be intentional or by accident. The macadamia nut, although popular in Hawaii, is actually native to Australia. It was intentionally introduced to the island of Hawaii by a man named William Herbert Purvis in 1881 to simply plant in his garden. Eventually, the nuts became commercialized and have become very popular ever since.

Homologous Structures

Homologous structures refers to the similarities in the anatomy of the forelimbs of mammals that derive from different species, yet function differently for each mammal. It is said that these similarities in structure is because the mammals share DNA from a common ancestor. The forelimbs that are continuously compared are of those of a human, dog/cat, whale, and bird. In this photo, a human arm and cat leg are compared. If the bone structures were examined, then it can be seen that they both have a humerus, a radius and ulna, carpals, metacarpals, and phalanges. However, the human's forelimb is used to perform activities like lifting. The cat, on the other hand, would utilize its forelimb for walking or running.

Gymnosperm Leaf

The leaves in this photo belong to a Cook Pine, which is a type of gymnosperm. Gymnosperms are vascular plants that grow exposed ovules and have thinner leaves, compared to the broader and flatter ones of an angiosperm. Typically, there are three types of gymnosperm leaf. There's needle-like seen on pine trees, awl-like like the ones on evergreens, and scale-like, which are like the ones in the photo. An advantage of this type of leaf is that they are able to conserve water, especially if the tree is in a drier area.

Frond

This is a photo of a small palm tree, whose leaves are called fronds. Fronds are the large, fanned out leaves of either ferns, palm trees, like the one in the photo. Frond leaves typically have fine, deep divisions, though some ferns and palms have finer divisions than the ones seen here. All frond have long stalks the support the blades. 

Flower Ovary

A flower ovary is the flower's female reproductive organ, also known as the gynoecium, which is in charge of producing ovules. After the ovary is fertilized, it begins to develop into a seed, while the flower itself transforms into a fruit. This is done so they may be dispersed elsewhere and continue growing. Though the location varies between different flowers, the ovary of the flower depicted here is the rounded end located at the base of the flower. 

Ethylene

Ethylene is a natural and odorless hormone found in most fruits, such as bananas, apples, and pears, that aids with ripening. It is also responsible for opening flowers and leaf shedding. It omits as a gas in trace amounts and is present throughout the fruit's life, even after its been cut off from its stem. This is why the banana in the photo appears overripe. The ethylene inside of it continued to promote ripening. 

Ectotherm

In this photo, the lizard seen here is basking in the sun for warmth because it is an ectotherm. Ectotherms are animals that rely on its environment's external sources of heat to regulate its internal body temperature, since they are unable to create heat internally like endotherms. Both endotherms and ectotherms need heat for energy and to perform cellular functions. Some examples of ectotherms are reptiles, like the lizard above, amphibians, invertebrates, and most fish. They warm up by "sunning", or absorbing the sun, and cool down under a shade. 

Cuticle Layer of a Plant

In this photo, the water droplets seen gathered upon the leaf are being repelled by the leaf's cuticle layer. The cuticle layer is a protective cover made up of lipid and hydrocarbon polymers, turning it into a waxy, hydrophobic film. It exists just above the epidermal cells. The layer's purpose is to protect the epidermal cells, ensuring the leaf doesn't lose an excess amount of water. This allows the leaves to conserve water in climates that are fairly dry. 

CAM Plant

Cacti, like the one above, and other plants like orchids and succulents are known as CAM plants. CAM plants are plants that are able to adapt to hot and dry climates through a special metabolic pathway that depends on a day-night cycle. For example, this cactus would open its stoma during the night to intake carbon dioxide and store it in its vacuoles in the form of Malic acid until daytime. During the day, the cactus will close its stoma and the Malic acid is decarboxylated and the carbon is fixed through the Calvin cycle. CAM plants also have the ability to conserve water due to their stoma being closed during the day, allowing them to survive even in the driest of environments.

Coevolution

Here is a photo of a bee pollinating a flower, an example of coevolution. Coevolution refers to the changes that occur within the genetic composition of two or more organisms that make them become dependent on one another. In this case, the bee has evolved to easily gather pollen and use the flower's pollen and nectar to feed its colony. In turn, the flower can spread its male gametes and reproduce faster via the bee as it visits other flowers. It has also evolved to develop unique characteristics that would attract more bees to it, like the bright colors this flower has.

C3 Plant

This is a tomato plant. Plants like these, temperate crops like wheat, and all woody trees are known as C3 plants. These type of plants utilize the Calvin cycle to break down carbon dioxide (CO2) during photosynthesis. When C3 plants, like this tomato plant, undergo photosynthesis, the CO2 will attach to the molecule RuBP during the Calvin cycle and produce a 3 carbon 3-PGA. One disadvantage this plant has is it is unable to survive in a hot and dry environment like C4 and CAM plants can. If this tomato plant were to be put in such a climate, it would end up closing their stoma, thus slowing down CO2 intake and photosynthesis and ultimately crop production. 

Commensalism

Commensalism is a symbiotic relationship between two organisms in which one organism benefits from the other, yet does not affect the host organism in any way. An example of this relationship can be seen here between this tree and the Spanish moss growing on it. The Spanish moss is a type of plant known as epiphytes. Epiphytes grow on other plants, yet are capable of photosynthesizing their own food. Therefore, the host plant, like this tree, is neither gaining or losing anything from its presence. However, the Spanish moss is able to capture more water, sunlight, and stability from growing on the tree.

Anther and Filament of a Stamen

The stamen is the male reproductive part of a a flower which consists of two parts called the anther and the filament. This  specific flower's anther is the curved, pollen covered tip on top of the slender stalk, which is the filament. The anther's function is to produce pollen to be used during reproduction. The job of the filament is to attach to the center of the flower and ensure that the anther is exposed to both the pistil and pollinators.

Adaption of a Plant

Plant adaptions are methods or specific characteristics of a plant that allow it to successfully survive and adapt to its given environment. For instance, the lily pads shown above have adapted themselves to survive in water. Their leaves float above the water to capture sunlight for photosynthesis and their roots extend and anchor to the soil below to stabilize themselves and absorb the soil's nutrients.

Animal With a Segmented Body

Segmentation refers to the repeated divisions of a animal's body, each specializing in their own individual function. Not only does segmentation allow easier mobility, the divisions also facilitate performing complex activities. This type of body structure is common in vertebrates, annelids, and arthropods, like ants. The ant depicted above has a segmented body that has three main parts: a head, a thorax, and an abdomen. The head has antennae that help the ant navigate. The thorax are where the head, abdomen, and legs attach to. The abdomen is the location of the ant's digestive and reproductive organs.