Nicolai Copernicus (1473-1543) radically changed our understanding of astronomy when he proposed that the sun, not Earth, was the center of the solar system. This led to our modern understanding of the relationship between the sun and Earth.
We experience seasons because the Earth rotates on an axis that's tilted in its orbit. That 23.5 degree tilt causes the different hemispheres to be at different angles to the sun at different times of the year.
At the same time that the Northern Hemisphere is entering summer, the South Pole is tilted away from the sun, and the Southern Hemisphere is starting to feel the cold of winter. The sun’s glancing rays are spread over a greater surface area and must travel through more of the atmosphere before reaching the earth. There are also fewer hours of daylight in a 24-hour period.
If the Moon happens to be too far from Earth for its disk to completely hide the Sun, an annular eclipse occurs. Because the Moon's orbit around Earth is slightly inclined with respect to the ecliptic, solar and lunar eclipses do not occur every month, but only a few times per year.
Cause of Eclipse
We have day and night because the Earth rotates. It spins on its axis, which is an imaginary line passing through the North and South Poles. The Earth spins slowly all the time, but we don't feel any movement because it turns smoothly and at the same speed.
Why we have day/night
Equinox: the time when the sun crosses the plane of the earth's equator, making night and day of approximately equal length all over the earth and occurring about March 21 (vernal equinox or spring equinox) and September 22 (autumnal equinox)
Solstice: either of the two times a year when the sun is at its greatest distance from the celestial equator: about June 21, when the sun reaches its northernmost point on the celestial sphere, or about December 22, when it reaches its southernmost point
Alfred Wegener was a German meteorologist and geophysicist who developed the first theory of continental drift and formulated the idea that a supercontinent known as Pangaea existed on the Earth millions of years ago. Continental drift is the gradual movement of the continents across the earth's surface through geological time.
Convergent: an actively deforming region where two (or more) tectonic plates or fragments of the lithosphere move toward one another and collide
Divergent: a linear feature that exists between two tectonic plates that are moving away from each other
Transform boundaries: two tectonic plates slide alongside each other (also known as a conservative boundary)
Convergent, divergent, and transform boundaries
The Juan de Fuca plate is just off the coast of Washington.
Rift Zone: a feature of some volcanoes, especially shield volcanoes, in which a linear series of fissures in the volcanic edifice allows lava to be erupted from the volcano's flank instead of from its summit
The Cascade Volcanoes were formed by the subduction of the Juan de Fuca, Explorer and the Gorda Plate (remnants of the much larger Farallon Plate) under the North American Plate along the Cascadia subduction zone. The Explorer Plate broke off from the Juan de Fuca plate between 5 and 7 million years ago. As it did, the Cascade Arc resumed and the modern Cascade and Olympic Mountains began to rise.
Mantle convection is the slow creeping motion of Earth's solid silicate mantle caused by convection currents carrying heat from the interior of the Earth to the surface. Convection currents in the magma drive plate tectonics. Large scale convection currents in the upper mantle are transmitted through the asthenosphere. Hot columns of mantle material rise slowly. At the top of the asthenosphere, the hot material spreads out and pushes the cooler material out of the way. This cooler material sinks back into the asthenosphere.
Subduction Zone: the biggest smash-up on Earth, marking the collision between two of the planet's tectonic plates, the pieces of crust that slowly move across the surface over millions of years; when two tectonic plates meet, one may slide underneath the other, curving down into the mantle
The Channeled Scablands are a barren, relatively soil-free landscape in eastern Washington, scoured clean by a flood unleashed when a large glacial lake drained. They are a geologically unique erosional feature of Washington.
Sedimentary: types of rock that are formed by the deposition of material at the Earth's surface and within bodies of water (sandstone)
Metamorphic: rock that was once one form of rock,but has changed to another under the influence of heat, pressure, or some other agent without passing through a liquid phase (marble)
Igneous: rock formed through the cooling and solidification of magma or lava (granite)
Stratification: a system or formation of layers, classes, or categories
Stratification in Rocks
If there was volcanic ash - which you can date very well - found in a fossil, you would be able to compare it with other fossils if they had the same type of volcanic ash, and infer the time period the fossils came from.
Living organisms die and their skeletons/shells build up layers on the Earth. They also dig holes in the ground allowing water to run into the ground. Aquatic animals build dams creating lakes. Living organisms eat vegetation promoting erosion. They also send roots into cracks that can break down mountains.
Sedimentary rocks are formed particle by particle and bed by bed, and the layers are piled one on top of the other. Thus, in any sequence of layered rocks, a given bed must be older than any bed on top of it. This Law of Superposition is fundamental to the interpretation of Earth history, because at any one location it indicates the relative ages of rock layers and the fossils in them.
Cell: The smallest structural and functional unit of an organism, typically microscopic and consisting of cytoplasm and a nucleus enclosed in a membrane. Microscopic organisms typically consist of a single cell, which is either eukaryotic or prokaryotic.
1) Animal cells don't have a wall, whereas plant cells do. 2) Animal cells are round, whereas plant cells are rectangular. 3) Animal cells don't have chloroplasts, whereas plant cells do. 4) Animal cells have one or more small vacuoles, whereas plant cells have one, large central vacuole taking up 90% of the cell's volume.
Animal vs. Plant Cells
Function of Cell Wall: It's main function is to provide rigidity, strength, protection against mechanical stress and infection. It also provides the cell with limited plasticity that prevents the cell from rupturing due to the tugor pressure. As the cell wall is cutinized it prevents water loss and also aids in cell-cell communication.
Function of Chloroplasts: Chloroplasts work to convert light energy of the Sun into sugars that can be used by cells. The entire process is called photosynthesis and it all depends on the little green chlorophyll molecules in each chloroplast.
Function of Vacuoles: Vacuoles are storage bubbles found in cells. They are found in both animal and plant cells but are much larger in plant cells. Vacuoles might store food or any variety of nutrients a cell might need to survive. They can even store waste products so the rest of the cell is protected from contamination.
Function of Muscle Cells: Muscle cells contain protein filaments of actin and myosin that slide past one another, producing a contraction that changes both the length and the shape of the cell. Muscles function to produce force and motion.
Function of Nerve Cells: Your nervous system contains millions of nerve cells, called neurons. Neurons are highly specialised to transmit messages from one part of your body to another. All neurons have a cell body and one or more fibres.
Function of Bone Cells: One function of the osteocyte might be the remodeling of the bonethrough growths of new arms on the cell. It is also known that osteocytes can secrete growth factors which activate lining cells or stimulate osteoblasts.
Tissues are made up of groups of cells that all have a similar function and structure. Some examples of tissues include muscles, bones, skin and the lining of the stomach, lungs and intestines. The lining of the stomach is just one of the many tissues that have joined together to form the organ, as it also contains muscles, mucus membrane tissue and many other tissue types. Different species of plants and animals have different types of cells and thus different types of tissues, organs and systems. In humans and other animals, there are four main types of tissues: connective, muscle, nerve and epithelial. Each of these groups can be further broken down, as there are a number of different tissues within each family. For instance, the human body contains three different types of muscle tissue and two types of nerve tissue. Furthermore, blood, bones and cartilage are all types of connective tissue.
Digestive System: The system by which ingested food is acted upon by physical and chemical means to provide the body with absorbent nutrients and to excrete waste products; in mammals the system includes the alimentary canal extending from the mouth to the anus, and the hormones and enzymes assisting in digestion.
Circulatory System: The system of organs and tissues, including the heart, blood, blood vessels, lymph, lymphatic vessels, and lymph glands, involved in circulating blood and lymph through the body.
Respiratory System: The system by which oxygen is taken into the body and an exchange of oxygen and carbon dioxide takes place; in mammals the system includes the nasal passages, pharynx, trachea, bronchi, and lungs.
Your systems work together by... The purpose of your digestive system is to take in food from your environment and break it down on both macroscopic and molecular levels. Through the process of digestion, you break large nutrient molecules into smaller ones that your intestine absorbs into the bloodstream. Cells then take up these nutrient molecules and use them to build new molecules and provide for their cellular energy needs. Cells can also store the molecules for later use. Your respiratory system takes in oxygen from the atmosphere and moves that oxygen into the bloodstream by allowing it to move across the membranes of the lungs into the blood vessels. The circulatory system then carries oxygen to all the cells in the body and picks up carbon dioxide waste, which it returns to the lungs. Carbon dioxide diffuses from the blood into the lungs, and you exhale it into the atmosphere.
Paramecium, are single-celled organisms. "Single-celled" means that a Paramecium has only one cell for its entire body. The inside of a paramecium is a jelly-like fluid called protoplasm. Bits of food and other materials float around in the protoplasm. They live in water, including lakes, ponds, streams, rivers, and puddles. Some can even live in the bodies of animals or in moist soil. Paramecium have tiny hair-like things, called cilia, all around the outside of their cell. Cilia are important, because they are how Paramecium move. By beating the cilia back and forth, the Paramecium can move through the water. Paramecium usually attach themselves to the bottom of the pond or stream, or to a plant. Sometimes they "swarm," which means that they all let go and swim around until they find a new place to attach. Paramecium reproduce by a process called binary fission. This means the Paramecium can split in half and become two new Paramecium. Paramecium eat algae, bacteria, other protozoans, dead plant and animal matter, and other tiny animals. They have something similar to a mouth, called a cytostome, to let food items into their bodies.
5) Sexual reproduction provides genetic diversity because the sperm and egg that are produced contain different combinations of genes than the parent organisms. Asexual reproduction, on the other hand, does not need sperm and eggs since one organism splits into two organisms that have the same combination of genes.
6) Adaptation: a change or the process of change by which an organism or species becomes better suited to its environment
7) Evolution: the process by which different kinds of living organisms are thought to have developed and diversified from earlier forms during the history of the earth
8) Species: a group of living organisms consisting of similar individuals capable of exchanging genes or interbreeding; the species is the principal natural taxonomic unit, ranking below a genus and denoted by a Latin binomial
9) Gene: a unit of heredity that is transferred from a parent to offspring and is held to determine some characteristic of the offspring
10) Genetic: of or relating to genetics, genes, or the origin of something
11) Sexual Reproduction: the production of new living organisms by combining genetic information from two individuals of different types (sexes); in most higher organisms, one sex (male) produces a small motile gamete that travels to fuse with a larger stationary gamete produced by the other (female)
12) Asexual Reproduction: a mode of reproduction by which offspring arise from a single organism, and inherit the genes of that parent only; it is reproduction which almost never involves ploidy or reduction
Animal Classification System
14) The importance of genetic diversity is it strengthens a population by increasing the likelihood that at least some individuals will be able to survive major disturbances, and it makes the group less susceptible to inherited disorders.
~Tropical Rain Forest: Precipitation - 250 cm/year. Little temperature variation/abundant moisture. Contains more species than other biomes.
~ Savannas: Precipitation 90-150 cm/year. Open, widely spaced trees, seasonal rainfall. Parts of Africa, South America & Australia.
~ Deserts: Precipitation 20 cm/year. Dry, sparce vegetation; scattered grasses. Parts of Africa, Asia, Australia, North America.
~ Temperate Grasslands: Precipitation: 10-60 cm/year. Rich soil; tall dense grasses. Central North America; Central Asia.
~ Deciduous forests: 75-250 cm/year. Warm summers, cool winters. Europe; NE United States; Eastern Canada.
1) Decomposers are organisms that break down dead or decaying organisms, and in doing so, carry out the natural process of decomposition.
2) Consumers are organisms, usually an animal, that feeds on plants or other animals.
3) Ecosystems arebiological communities of interacting organisms and their physical environments.
4) Producers are autotrophic organisms that serve as sources of food for other organisms in the food chain.
5) The food chain is a hierarchical series of organisms that are each dependent on the next as a source of food.
6) Boitic is of, relating to, or resulting from living things, especially in their ecological relations.
7) Abiotic is physical rather than biological; not derived from living organisms.
8) Adaptation is a change or the process of change by which an organism or species becomes better suited to its environment.
9) Biotic factors in a wetland ecosystm are turtlehead flowers, water, trees, butterflires, competition, bacteria, carrying capacity, plaintain, ash, and the false foxglove.
10) Abiotic factors in a wetland ecosystem are sunlight, air, climate, soil, water, rocks, and temperature.
11) Sun --> algae→pond snail→bullfrog→northern water snake→great blue heron
12) Energy enters the ecosystem food chain in the form of sunlight.
13) The arrows in #11 represent how the organisms gain energy. (In most cases) they eat the organism in front of themselves.
14) Some organisms would die if one element of the food chain were to be eliminated. In some cases, there would be nothing for the primary consumers to eat, and they would die off. Then the secondary consumers would die off because they would have nothing to eat. Most organisms would eventually die from starvation.
15) Wetlands improve water quality through filtering (water runoff from higher dry land before the runoff reaches open water.)
16) Wetlands offer flood protection by acting as natural sponges that trap and slowly release surface water, rain, snowmelt, groundwater and flood waters. Trees, root mats, and other wetland vegetation also slow the speed of flood waters and distribute them more slowly over the floodplain.
17) Wetlands protect shoreline from erosion by... The ability of wetlands to control erosion is so valuable that some states are restoring wetlands in coastal areas to buffer the storm surges from hurricanes and tropical storms. Wetlands at the margins of lakes, rivers, bays, and the ocean protect shorelines and stream banks against erosion. Wetland plants hold the soil in place with their roots, absorb the energy of waves, and break up the flow of stream or river currents.
18) Wetlands provide habitat for wildlife by... For many animals and plants, like wood ducks, muskrat, cattails, and swamp rose, inland wetlands are the only places they can live. Beaver may actually create their own wetlands. For others, such as striped bass, peregrine falcon, otter, black bear, raccoon, and deer, wetlands provide important food, water, or shelter. Many of the U.S. breeding bird populations-- including ducks, geese, woodpeckers, hawks, wading birds, and many song-birds-- feed, nest, and raise their young in wetlands.
19) Wetland offer benefits by... Many of the nation's fishing and shellfishing industries harvest wetland- dependent species; the catch is valued at $15 billion a year. In the Southeast, for example, nearly all the commercial catch and over half of the recreational harvest are fish and shellfish that depend on the estuary- coastal wetland system.Louisiana's coastal marshes produce an annual commercial fish and shellfish harvest that amounted to 1.2 billion pounds worth $244 million in 1991. The nation's harvest of muskrat pelts alone is worth over $70 million annually.