Science

ECOSYSTEMS

An ecosystem is an area where living and nonliving things interact.

Biotic Factors - all living and once living things in an ecosystem

Abiotic Factors - all nonliving things in an environment

A national park is an ecosystem being saved for its: special scenery, history, wildlife, and for the enjoyment of future generations.

Food chain - one example of the order of who eats who in an ecosystem

Food web - the best way to show how an organism really eats

Parts of a Food Chain: Producers - make their own food

The flow chart of ecosystems: 1.Ecosystems include all living and nonliving things. Next are 2.communities in ecosystems - these are just the living organisms. The it goes to 3.populations - which are groups of the same organisms (like all the birds) and finally the smallest group are 4. species. Species - organisms that have the same physical characteristics and can produce young together.

Consumers - organisms that eat other organisms

Types of Consumers: 1) Herbivores - eat only plants. 2) Carnivores - eat only meat. 3) Omnivores - eat both plants and meat 4) Scavengers - eat carrion (things that are dead) or decaying matter

Predator - an organism that hunts, kills, and eats another organism

Prey - an organism that gets hunted, killed, and eaten

The lynx and the hare have been studied in their predator-prey relationship. Scientists have found they need each other to keep their populations in check.

The 2 things that change ecosystems the most are human activity and natural disasters/

Symbiosis - a long term relationship between 2 different species. There are 3 kinds of symbiosis: 1) mutualism (pals)-this is when both species get something good in the relationship - like bees and flowers. 2) commensalism (hitchhiker)-this is when one species gets something positive and the other isn't affected...like the remora fish riding along on the shark eating scraps of the shark's meal. 3) parasitism (pickpocket) - one species benefits and the other is harmed-like a tick on a person

parasite - the organism that lives on, feeds upon, and harms another species

host - the organism that is fed upon or supplies the food

Exploring the Night Sky

constellation - a group of stars that forms a pattern in the night sky

The Greeks, Romans, and Native Americans named most Northern Hemisphere constellation after characters from stories and animals. The Southern Hemisphere constellations were named by explorers on ships. Some were named after tools on ships and new creatures they saw in their travels.

Familiar Constellations: Ursa Major (big bear). Part of Ursa Major is nicknamed "The Big Dipper." The pointer stars in the Big Dipper point to Polaris, the North Star - which is at the end of the handle in Ursa Minor (the little bear). Polaris is located directly over the north pole and is known as the "Pole Star."

If you keep pointing past Polaris, you will reach Cepheus the king (shaped like a simply drawn house). To the right of Cepheus is Cassiopeia, the queen - who is shaped like the letter W. Going back to the Big Dipper, if you follow the arc of the handle, you will arrive at Arcturus - a bright star found in the constellation Bootes (the Herdsman) - who is shaped like a kite. At Bootes' right shoulder is Corona Borealis - the crown. Under the bottom of the Big Dipper is Leo the lion - known for its backwards question mark shaped head. When looking at the Big Dipper in the winter months, if you turn around, you will see Orion - the great hunter- in the southern sky. Follow his belt stars down to find Sirius, the brightest star in our night sky. Sirius is in the dog constellation called Canis Major. The tail of Draco, the dragon, is found between the dippers. Cygnus, the swan, if found near the head of Draco.

Why do stars appear to move? The earth spins! One rotation takes 24 hours and is called a day. The earth also travels around the sun- one revolution takes 365 days - or one year.

Other objects in the night sky: PLANETS- a planet is a large object that orbits a star and does not make its own light. They don't twinkle, they appear disc shaped and move differently than the constellations. "Planet" means wanderer of the night sky. STARS -a star is a huge globe of hot gases that makes its own light. COMETS - A comet is like a frozen snowball. It is made of frozen water, dust and debris, ammonia, and methane. A comet orbits a star. It's tail is created by the heat from the sun and the winds from the sun. Halley's Comet comes every 76 years. METEROID -an object the size of a grain of sand to the size of a boulder that is traveling in space. METEOR-chunks of rocks or comets that burn up as they come into our atmosphere. We know them as "shooting stars" or "falling stars." METEORITE -a meteor that hits the Earth.

2 Types of Telescopes - 1. refracting - uses 2 glass lens 2. reflecting - uses mirrors

History of the Telescope - 1. 1600s - Hans Lippershey created the first known telescope 2. Galileo made a stronger telescope and used it to study space 3. Isaac Newton invented the reflecting telescope 4. Hubble Space Telescope - placed above the earth in space 5. In 2021 The James Webb Telescope was launched and placed far past the moon

Work and Machines

A machine is a device that makes work easier.

*A machine takes away some effort force but you still have to work.

Simple Machines

Inclined plane - an inclined plane is a simple machine with a sloping surface.

Some inclined planes are steep. They are a shorter distance but require more effort force. (Trail A) Others are like ramps and are a longer distance to use but you use less effort force. (Trail B) The good thing about using inclined planes(ramps)is that you use less effort force, The bad thing is that you have to go a longer distance.

Inclined planes that we move around are: 1. wedges - objects that split objects apart and 2. screws

Levers - a lever is a simple machine made up of a bar that turns around a fixed point

fulcum - the fixed point that the lever bar is attached to. There are 3 types of levers. See chart to the left

Wheels and Axles - a simple machine made up of 2 wheels which turn around a fixed point. A wrnech works like a wheel. A gear is a wheel with teeth that takes away effort force.
Pulleys - a wheel that has a rope or chain that passes around it. There are 3 types of pulleys. 1.Single fixed pulley (one pulley that is attached to something). This is like a first class lever because the fulcrum is in the middle and the forces go in opposite directions. 2. Single movable pulley - the pulley is free to move along the rope (like a zipline) 3.Pulley combination - when 2 or more pulleys are used together to take away more effort force

Compound Machine - a machine made up of 2 or more simple machines used together (like a car).

Energy Chapter 1

Energy is the ability to do work and cause change.

If something is using energy, it will cause a change in one of these things: its speed, direction, position, or temperature

Kinetic energy - the energy of motion

Potential energy - stored energy

Types of Energy: wind, water, solar, geothermal, sound, chemical, heat, light

Energy on a Roller Coaster - potential energy and kinetic energy move opposite of each other. As you go higher on the hill, your potential energy goes up. It is highest at the top of the tallest hill. When you are going down, kinetic energy goes up. Kinetic energy is highest at the bottom of the hill.

Electromagnetic Energy - this is all the types of energy from the sun. It travels to earth through empty space as waves. We can only see white light. Ultraviolet radiation gives us sunburns, infrared gives us heat, and X-rays are used in the medical field.

Radiation - the transfer of heat energy in waves

Medium - something that carries energy

Force - a pull or a push

*Forces are needed to set an object in motion and to stop an object in motion.

Effort force- the force you use to get an object to move

Resistance forces are the forces we battle against every day. They are: 1. gravity 2. friction

You can reduce friction by: 1. Using rolling friction (wheels) and 2. Using a lubricant

Calorie - the energy people get from food

Mass - the amount of matter in an object

speed - how fast an object moves

velocity - the speed along with the direction the object is moving

acceleration - an increase in the speed

deceleration - to slow down the speed

inertia - when an objects resists against a change in its motion

Galileo studied inertia (in-er-sha)

Sir Isaac Newton studied energy and motion. He made the 3 Laws of Motion.

Work is only done if a force moves an object. No movement means you haven't done any work.

The formula for work is: Work = force times distance

Work (Joules) = force (N) X distance (m)

Energy is needed to do work!

Ch. 2 The Solar System

Our solar system contains: 1: the sun 2: the planets 3: the moons 4: comets 5: asteroid belt

The asteroid belt separates the inner planets from the outer planets.

The inner planets are small, rocky, have no rings, have few satellites, and they are warmer. The outer planets are giant, made of gases, have rings, have many satellites and are colder. They all orbit the sun.

Early views of the solar system:

Ptolemy thought that all things revolved the earth. He called it the geocentric model. He was wrong.

Copernicus believed that all things in the solar systen revolved around the sun. He called it the heliocentric model. He was right. Galileo proved this with his telescope.

Stars

The 4 differences in stars are: 1. size 2. temperature 3. color 4. brightness

Color and temperature are related. Blue is the hottest (Rigel), blue-white is very hot (Sirius), white is very hot. Yellow is average (sun), orange-red is cooling (Arcturus), and red is the coolest color (Betelgeuse).

All stars make energy by turning hydrogen into helium.

Scientists measure the huge distances

in space by using a unit called a light year. A light year is the distance that light travels in a year.

Universe - everything that exists

Galaxy - a HUGE neighborhood of stars

We live in the Milky Way galaxy which has at least 100 billion stars/ There are 100 billion other galaxies which each have 100 billion stars in them - WOW!

Edwin Hubble studies galaxies. He classified them into 3 main groups:

elliptical 2. spiral 3. irregular

Life in Space - you float! Humans grow taller, muscles like your heart grow weaker, bones lose calcium, your face swells, and yo are exposed to high levels of radiation.

Extraterrestrial - from beyond earth

Ch. 4 FLOWER POWER

Chapter 4 Flower Power

The job of every flower is to reproduce and make seeds.

Flowers are colorful to attract bees, insects, hummingbirds, fruit bats, and even people to them.

Parts of a flower: Female parts: pistil (main female part), stigma (sticky part at the top), style (the narrow top under the stigma), ovary (turns into the fruit), and ovules (becomes the seeds) Male parts: stamen (holds up the anthers) and anthers (holds the pollen. The other parts are the petals, the sepals (leaves that once held the bud shut) and the stalk (the thick part of the stem under the flower).

6 Steps of Pollination

Pollen lands on the sticky stigma with the help of a pollinator
A tube grows down the style
Fertilization takes place when the tube touches the ovary
4. The ovary grows bigger.
Ovules form inside the ovary
The fruit ripens and the seeds are released

Seed Dispersal - the scattering away of seeds from the parent plant

Seeds are dispersed by - wind, water, shape of the seed, seed pod explosion,seeds sticking to things, carried away by animals, and bird/animal digestion

The Story of a Tree Seed

Germination - a seed falls to the ground. It sprouts and roots grow down.
Seedling - a green stem appears and you can see true leaves
Sapling - bark forms and it grows taller
Tree - it measures 10cm around in diameter
Mature tree - it makes seeds

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Ch. 3 Plant Processes

Photosynthesis - the word "photo" means light and "synthesis" means to join together

Here's how it works:

Mr. Chlorophyll needs water and carbon dioxide. He uses light energy to change those 2 things into 2 new things - glucose (the name for a plant's food) and oxygen,

It looks like this: H2O + CO2 -changed by light energy - to make glucose + O2 (the 2's are supposed to hang below the line.)See photo on the left.

A stoma is a little hole found on the underside of a leaf. More than one stoma are called stomata. Three things use the stomata. Carbon dioxide comes in for photosynthesis. Oxygen leaves in photosynthesis. And water goes out in tranpiration (see below).

Oxygen is made to break down thea glucose in the plant before going out the stomata to us.

70% of our oxygen comes from plants living in the ocean so we should keep our oceans clean.

Transpiration - the way a plant gets rid of extra water through the stomata.

On hot, dry days, the stomata would almost be closed to keep the water inside the leaf.
On wet, rainy days, the stomata would be open to get rid of any extra water.

A tropism is the plant's response to conditions in the environment around it. There are 4 types of tropisms:

geotropism - the roots always grow down towards the center of the Earth and the stem grows up
phototropism - plants grow towards the light
hydrotropism - roots grow towards the water
thigmotropism -tendrils on the plant help it climb higher to the sunlight

Plants and the Food Chain

all living things are linked in a food chain
producers start most food chains
3 parts in a food chain: producers, consumers (have to eat other things to get energy) and decomposers (eat dead, decaying things at the end of a food chain)
a food web is a better description of how things really eat in the world

CHAPTER 2 LEAVES!

The job of every leaf is to make food for the plant.

Photosynthesis - this is the way a plant is able to make food

2 Types of tree leaves:

Broad leaf (this falls off the tree each fall)
Needle-like leaf (grows on a conifer)

Parts of a tree leaf:

margin - the outside edge
petiole - the part that holds onto the tree (found at the base of the leaf)
blade - the flat inside of the leaf
veins - carry water
lobes - the cut out sections on some leaves

Leaves - Broad Leaves are either simple, compound, double compound, or palmately compound.

Conifer trees are either needle-like or scale-like

Leaves can be attached opposite (right across from each other) or alternate (taking turns going up the petiole)

Margins are either smooth, lobed, or toothed.

The base of a leaf is where the petiole touches the bottom of the leaf. it can be: V-shaped, rounded, uneven. heart-shaped, or flat.

Roots

2 jobs: 1) to absorb water and nutrients. 2) to anchor the plant

There are 2 kinds of roots - fibrous roots (they spread out) and tap roots (they have one main root - like a carrot)

Inside a root: the outer part of the root (the skin) is the epidermis, the cortex is the stored food, and the xylem carried water up and the phloem carries water down.

Roots have root hairs and at the bottom there is a root cap to push into the soil.