Anther and Filament of a Stamen

The anther and filament are the two parts of the stamen. The anther contains the male reproductive cell, pollen, and the filament holds the anther.

The anthers and filaments are very prominent on this flower. The parts of one stamen are labelled.

Pollen

A powdery substance that is produced in the anther of a flower or in a male cone. Pollen is made up microscopic grains, each of which contains a male gamete. 

The anthers of this flower produce the pollen. In order for fertilization to occur, the pollen must be transported to the stigma.

Exoskeleton

A hard encasement on the surface of an animal that provides protection and points of attachment for muscles.

The exoskeletons of crayfish allow the crustaceans to move and provide protection from predators .

Modified Root of a Plant

The roots of many plants have adapted to provide better support for the plant or to better obtain and store nutrients.

Sweet potatoes are examples of roots that store nutrients. The plant can use the stored water and nutrients if conditions become unfavorable.

Cuticle Layer of a Plant

A waxy covering on the surface of leaves and stems that prevents terrestrial plants from becoming too dry.

The waxy covering of the leaves can be easily seen on this plant. All above-ground parts of the plant are covered by the cuticle in order to prevent water loss. Openings in the leaves, called stomata, open and close to allow CO2 and oxygen to be exchanged between the environment and the plant.

C4 Plant

In C4 plants, the Calvin cycle is proceeded by reactions that fix carbon from CO2 into a four-carbon sugar.

Corn is a an example C4 plant. C4 plants are more efficient than C3 plants and have adapted to high daytime temperature and intense sunlight.

Population

A localized group of individuals of the same species that can interbreed and produce fertile offspring.

This wasp nest is home to a population of wasps. 

Modified Leaf of a Plant

Many plants have adapted to have leaves that aid in water retention, defense, or growth and reproduction. Some leaves trap insects to provide the plant with nitrogen.

This succulent plant has modified leaves that allow it to survive in dry climates. The leaves retain water but also minimize surface area and water loss.

Tropism

Growth response that results in movement toward or away from stimuli.

This plant grows up the side of the house and wraps around the gutter. This is an example of thigmotropism, the curvature of a plant in response to a touch stimulus.

Fermentation

An anaerobic process in which a limited amount of ATP is produced from glucose. Fermentation produces a characteristic end product.

This runner's muscle cells are carrying out lactic acid fermentation. When the muscles do not have enough oxygen for aerobic respiration, lactic acid fermentation occurs .Lactic acid, which may be responsible for muscle soreness, is produced as a byproduct. 

CAM Plant

Plants that use crassulacean acid metabolism, an adaptation for photosynthesis in arid conditions.

This is a photo of an orchid. Many orchids obtain water from the air or rain rather than from their roots. This means that, like plants in arid climates, orchids must conserve water. Plants that use crassulacean acid metabolism acquire CO2 at night when the stomata are open. During the day, the Calvin cycle takes place and the stomata are closed to prevent water loss.

Adaptation of a Plant

Feature that allows the plant to live in a particular place.

Cacti have adapted to withstand the desert climate by minimizing water loss and maximizing water intake. Specifically, these plants have stems that can store water, spines rather than leaves, and large root systems. 

Xylem

Vascular plant tissue consisting primarily of dead cells that conducts water and minerals upward from the roots.

Another function of xylem, which contains woody fibers, is support. The word xylem comes from the Greek word for wood, xulon. The log in the photo is made of xylem.

Seed Dispersal

The transport of seeds away from the parent plant.

The seeds of this plant are transported by the wind. Seeds of other plants are dispersed by animals or by the plant itself.

Pollinator

Pollinators move pollen from the anthers to the stigma in order to accomplish fertilization.

Bees are responsible for the pollination of many plants. These insects pollinate flowers as they collect nectar and pollen for their survival.

Genetically Modified Organism

An organism that has artificially acquired one or more genes.

More than 90% soybeans are genetically modified. Crops are genetically modified to be resistant to pesticides. This means that farmers can spray pesticides on the crop without killing it.

Flower Ovary

The portion of the carpal in which ovules (reproductive cells) develop. 

This pepper plant shows multiple flower ovaries at various stages of development. The flower ovary develops into the fruit.

Endotherm

Metabolic processes produce the heat needed to maintain a stable body temperature.

This dog can maintain a stable body temperature without heat from external sources. The body temperature of endotherms is typically higher than the surrounding environment. Dogs maintain a body temperature of about 102.5 degrees Fahrenheit.

Ectotherm

An organism that uses heat from external sources to regulate its body temperature.

In nature, the sun provides the heat that lizards need to regulate their body temperature. This lizard, as well as other ectothermic pets, requires a heat lamp.

Dominant vs. Recessive Phenotype

If a dominant allele is present, it will mask the effect of the recessive allele.

This dog has one brown eye and one blue eye. The brown eye color is dominant and the blue eye color is recessive.

Incomplete Dominance

The phenotype of the heterozygote offspring is intermediate between the homozygous parental phenotypes. Offspring displays a mixing of parental traits.

The light purple flowers result from a mixing of parental traits. The light purple shade is a mix of the darkest and lightest shades.

Codominance

Codominance occurs when the phenotypes of both alleles are exhibited. The offspring has a third phenotype and displays both parental traits.

These pink and white flowers show traits of both pink flowers and white flowers.

Bilateral Symmetry

An organism is said to have bilateral symmetry if it has two equal and opposite halves.

The body of this donkey is bilaterally symmetrical. As shown, a plane could divide the donkey into two equal and opposite halves.

Autotroph

Autotrophic organisms obtain food molecules without eating other organisms or substances derived from them. 

These sunflowers are autotrophs. They use energy from the sun to make organic molecules from inorganic molecules.

Amniotic Egg

A shelled egg in which the embryo develops within a fluid-filled amniotic sac and is nourished by yolk.

Amniotic eggs are produced by reptiles, birds, and egg-laying mammals. This is a photo of two chicken eggs.