Praxis Science Flashcards
Nitrogen Fixation
Nitrogen fixation is when ammonia is produced from atmospheric nitrogen.
Which layer of the atmosphere contains the ozone layer?
The stratosphere contains the ozone layer, which is responsible for blocking UV rays.
Meteorite
A meteorite refers to a meteor that has made its way to Earth and has landed on its surface.
Newton’s First Law (Law of Inertia):
Definition: An object will stay at rest or move in a straight line at a constant speed unless acted upon by an external force.
Example: If you slide a book across a table, it will eventually stop because of the force of friction acting on it.
Newton’s Second Law (Law of Acceleration):
Newton’s second law of motion states the acceleration of an object is dependent on the net force acting on the object and the mass of the object.
Example: If you push an empty shopping cart, it will accelerate faster than a full shopping cart because the empty cart has less mass.
Newton’s Third Law (Action and Reaction):
Definition: For every action, there is an equal and opposite reaction.
Example: When you jump off a small boat onto a dock, the boat pushes back in the opposite direction, making it move away from the dock.
Newton’s Fourth Law (Universal Gravitation):
states that every object in the universe pulls on every other object with a force called gravity.
The reason we stay on the ground and don’t float away is because the Earth’s gravity pulls us towards its center.
What is a eukaryotic cell?
A eukaryotic cell is a type of cell that has a nucleus and other special parts called organelles.
What is the basic unit of life?
the cell
What type of organelle in the cell synthesizes proteins?
Ribosomes
What is the function of the golgi apparatus in the cell?
The Golgi apparatus helps package and secrete proteins. A sorting or distribution center for proteins. It receives proteins from the endoplasmic reticulum, or ER.
What is the difference between smooth and rough ER and what is their function within the cell?m
A rough tubular maze of membranes.
The smooth ER is smooth is not studded with ribosomes. It creates lipids/fats. Acts as a detoxification center. (Emergency room where fat lipid babies are made)
The rough ER is covered in ribosomes. Ribsomes create proteins and the rough ER “packages” them to be transported.
What is histology the study of?
The study of tissues
Name the four main types of tissues in the human body.
Epithelial tissue
Connective tissue
Muscular tissue.
Nervous tissue
What are the three types of muscular tissue?
Skeletal
Smooth
Cardiac
What are examples of connective tissue?
bone & cartilage
blood & fat ( adipose connective tissue)
Which types of muscular tissue are involuntarily controlled?
Smooth, cardiac
What type of muscle makes up the Stomach and intestines?
Smooth muscle tissue
What are plant tissues called and what are their types?
Tissue Systems
Epidermis - make up plant leaves
Vascular tissue - transport food and water to the plant via the stem and roots
Ground tissue - makes energy for the plant via photosynthesis
Specific epithelial tissues are categorized by what two things?
The individual cell shape and how many cell layers thick the tissue is.
What is the integumentary system made up of?
skin, nails, hair, subcutaneous fat
What is the main function of the human body’s integumentary system?
To protect the body.
- helps to shield the body from environmental changes and pathogens.
- help regulate temperature homeostasis.
What are the parts of the human body’s endocrine system?
all hormone producing organs or glands, thyroid, pitutatary, adrenals, pancreas etc.
What is the purpose of the human body’s endocrine system?
It acts as a messaging system, producing hormones which are sent through the body to help regulate other organ activities.
What is the correct order of biological organization of the following (from largest to smallest): Communities, population, biosphere, eyosystem.
Define each one.
Biosphere: All of Earth and its atmosphere.
Ecosystem: All of the rainforests on Earth.
Community: All communities of primates within the rainforest.
Population: All members of the community whose species is the golden tamarin.
What are the qualities that define a living thing?
made up of cells - at least one cell must exist for it to be living
movement - it must move around
use energy and get energy from a source - it must be able to get energy, convert it to a usable form, and use it
grow and develop - it must change in characteristics and get bigger
reproduction - it must make copies of itself one way or another
response to stimuli - it must react to the environment at some point
homeostasis - it must seek to maintain a stable internal environment
What is acceleration is terms of Newton’s second law?
This rate at which velocity changes is defined as acceleration. An object that changes direction or speed is accelerating. The change in speed can be increasing or decreasing to be considered acceleration. For example, a car that maintains a speed of 25mph but changes direction is considered accelerating. A car that maintains due north but either increases or decreases speed is considered accelerating.
What is velocity in terms of Newton’s second law?
Velocity is defined as the speed of an object in a given direction.
Two examples of velocity include a car traveling at 25 mph north or a plane flying at 575 mph in the northeast direction.
An object that changes speed or direction has a change in velocity.
What is inertia in terms of Newton’s first law?
Inertia is the resistance of an object to a change in motion.
For example, an elephant and rabbit are running at the same speed. The elephant will have greater inertia than the rabbit because the force needed to change the motion of the elephant will be greater than the force needed to change the motion of the rabbit.
What is the formula for acceleration?
What is simple harmonic motion? Give an example.
Simple harmonic motion is a repetitive, or periodic, motion where the restoring force is proportional to the displacement from an equilibrium position.
It includes things like pendulums and masses bobbing up and down on a spring. As you stretch the spring, there is a restoring force that wants to pull it back to where it began, and that force gets stronger the more you pull.
What is projectile motion? Give an example.
Projectile motion is motion that involves two dimensions, such as that which occurs in a water fountain.
When you release a projectile, like a cannonball, a bullet from a gun, or a baseball coming off a bat, it moves in an up-and-down dimension and a forwards-and-back dimension.
What are the defining characteristics of plasma as a state of matter?
Super Hot Gas: Plasma is a super hot gas where atoms are split into free-moving electrons and ions.
Glows: Plasma often glows with bright colors, like in neon signs and lightning.
Electricity: Plasma can conduct electricity, which means it can carry electric currents.
Magnetic: It can be moved and shaped by magnets.
Space Stuff: Plasma is found in stars, including the sun, and in space.
High Energy: It has a lot of energy because of the high temperatures.
Charged Particles: Plasma is made up of tiny charged particles that move around freely.
What is circular motion? Give an example.
Circular motion is, unsurprisingly, motion in a circle.
For example, imagine a ball being whirled above your head on a string or a satellite orbiting the Earth.
When an object is moving in a perfect circle at a constant velocity, we have different equations we can use to describe the motion.
What are unbalanced forces in terms of physics?
Unbalanced forces are forces on an object in opposite directions that are not equal. They cause an object to change velocity. Velocity is speed in a given direction.
What is mass in terms of Newton’s laws of physics?
Mass is defined as the quantity of matter in an object.
What is net force is terms of Newton’s second law?
Net force is defined as the sum of all forces acting on an object.
What is force in terms of Newton’s first law?
A force is a quantity with magnitude and direction. Forces are often represented by arrows. This image shows the two forces acting on the object. The size of the force is represented by arrow length. The net force on this object is zero because the length of arrows is equal in both directions representing a balanced force. According to Newton’s first law, this object will remain at rest until the net force is no longer balanced. An unbalanced force is a force applied in opposite directions that are not equal in size or magnitude.
What unit is net force measured in?
Newtons (N)
What equation represents Newton’s second law?
Newton’s second law states that the net force of an object is the product of its mass (m) and acceleration (a). This force equation relates: force mass x acceleration:
What is linear motion?
Linear motion is motion in a straight line. It’s also called 1-D motion, because you’re moving in one dimension.
Linear motion is generally the easiest to describe: you just have one graph for displacement over time, one graph for velocity over time and one graph for acceleration over time.
A car driving on a perfectly straight road is a good example of linear motion.
What is the physics equation for WORK?
Work = force x distance
amount of force (N)
the distance displaced (distance - m)
the cause of the displacement
What three conditions must be met for WORK (work = force x distance) to happen?
What is the physics equation for POWER?
What unit is POWER measured in?
Watts
(Remember work is measured in joules)
What are the three types of fossil fuels?
Coal, natural gas, and oil
End product of animal and plant remains stewing deep beneath the earths surface
What is mechanical energy?
moving matter and energy moving through a medium (the matter that waves travel through)
What is a photon?
A photon is a tiny particle of light. It has no mass and travels at the speed of light, carrying energy. For example, the light from the sun is made up of countless photons that travel to Earth and make it bright.
What is carbon sink?
A carbon sink is anything that removes more carbon from the atmosphere than it gives off.
Three sources of carbon sink are the ocean, soil, and plants.
What are the steps of the scientific method?
Olivia’s quirky hamster eats all cookies.
Who is John H. Ostrom and what is his impact on paleontology?
John H. Ostrom was an influential American paleontologist best known for his groundbreaking work on the relationship between dinosaurs and birds. His impact on paleontology includes:
- Dinosaur-Bird Connection: Ostrom’s study of the dinosaur Deinonychus in the 1960s led to the revolutionary idea that some dinosaurs were more closely related to birds than to reptiles. This challenged the traditional view and provided evidence that birds are the modern descendants of theropod dinosaurs.
- Feathered Dinosaurs: His work laid the foundation for the discovery of feathered dinosaurs, supporting the theory that feathers and other avian characteristics evolved in theropod dinosaurs before the appearance of modern birds.
- Revising Dinosaur Biology: Ostrom’s research contributed to a new understanding of dinosaur behavior and physiology, suggesting they were active, warm-blooded creatures rather than the sluggish, cold-blooded reptiles they were once thought to be.
Ostrom’s contributions significantly advanced our understanding of dinosaur evolution and bridged the gap between dinosaurs and birds, transforming the field of paleontology.
What are the stages of the water cycle?
Evil crooks pay cash.
- Evaporation: Water from oceans, rivers, lakes, and even plants turns into water vapor and rises into the air due to the heat from the sun.
- Condensation: The water vapor cools down as it rises and turns back into liquid water droplets, forming clouds.
- Precipitation: The water droplets in the clouds become heavy and fall back to the Earth as rain, snow, sleet, or hail.
- Collection: The water collects in bodies of water like rivers, lakes, and oceans, and the cycle starts again.
What is a mantle plume?
A mantle plume is an upwelling of abnormally hot rock within the Earth’s mantle. This hot rock rises from deep within the mantle, possibly from near the core-mantle boundary, and can cause volcanic activity when it reaches the Earth’s surface.
An example of a mantle plume is the one beneath Hawaii, which creates the volcanic islands in the middle of the Pacific Ocean.
What are the different types of biodiversity? Describe each.
What are infrared waves?
Infrared waves are a type of electromagnetic radiation with wavelengths longer than visible light but shorter than microwaves. They are often associated with heat, as objects emit infrared radiation based on their temperature.
For example, infrared waves are used in remote controls for TVs and in thermal imaging cameras to see heat patterns.
