Exploring the Fundamentals of Science and Nature
1st Evaluation: Matter and Its Properties
Matter
Matter is anything that has mass and occupies volume. A physical quantity is an attribute of substances that can be measured.
Mass
Mass is related to the amount of material a substance has.
Volume
Volume is the space occupied by a body.
Density
Density (d) is the relationship between the mass and volume of a body.
Pure Substances and Mixtures
A pure substance has well-defined and constant properties.
Mixtures
Mixtures have less defined properties.
- Heterogeneous Mixture: Components can be distinguished visually and composition varies.
- Homogeneous Mixture: Components are indistinguishable visually and composition is uniform.
Solutions
Solutions are homogeneous mixtures formed by two or more components.
Separation Techniques
- Heterogeneous: Settling, filtration, magnetic separation.
- Homogeneous: Crystallization, distillation.
Atoms and Molecules
An atom consists of a central nucleus containing protons (+) and neutrons (no charge), with electrons (-) orbiting around the nucleus.
Molecules are formed by the union of several atoms in specific numbers.
Lattices are formed by the union of an indefinite number of atoms in an orderly manner in all three dimensions.
Pure Substances: Elements and Compounds
An element is a pure substance formed by a single class of atoms.
A compound is a pure substance made up of different atoms.
Chemical Reactions
A chemical reaction is a process where one or more substances (reactants) with defined properties are transformed into other substances (products) with different properties.
2nd Evaluation: Earth and Its Systems
Rotation
The Earth’s rotation on its axis causes day and night.
Parallels
Parallels are circles that intersect the rotation axis perpendicularly.
Equator
The Equator is the parallel that divides the Earth into two hemispheres.
Meridians
Meridians are semicircles that converge at the poles.
Greenwich Meridian
The Greenwich Meridian is the reference meridian.
Latitude
Latitude is the distance between any point and the Equator.
Longitude
Longitude is the distance between any point and the Greenwich Meridian.
Translation and Seasons
The Earth’s translation around the Sun, combined with the tilt of its axis, causes variations in the amount of sunlight received, leading to the seasons.
Earth’s Spheres
The Earth’s outer layers consist of the atmosphere, hydrosphere, lithosphere, and biosphere.
Vertebrates
Main Features
- Bilateral symmetry
- Body divided into head, trunk, and tail
- Two pairs of limbs
- Internal skeleton
- Vertebral column
Reproduction and Systems
Breathing
Respiration can be through gills, lungs, or sometimes skin (cutaneous respiration).
Circulation
The heart can have two or four chambers. Closed circulation in reptiles, birds, and mammals. Double circulation in reptiles, birds, and mammals. Complete circulation in mammals and birds.
Reproduction
Separate sexes, sexual reproduction (external or internal fertilization). Oviparous, viviparous, or ovoviviparous.
Classification
: fish, amphibians, reptiles, birds and mammals fish fish the largest group of aquatic vertebrates are your body has tapered scales and utensils in their limbs are shaped fins (the pair are responsible for the direction of motion and produce the odd forward) vegiga most have frlotar allowing them to swim at different depths are lateral gill breathing lienee its heart is divided into 2 cavities an atrium and a ventricle are oviparous (most) and are ectothermic. amphibians: Amphibians most crepuscular or night took the first vertebrates to terrestrial life, its body is divided into Cavez trunk and tail tetrapods possess four limbs are the Most are oviparous and have metamorfotis and are ectothermicreptiles: terrestrs mind first vertebrates total dry skin with scales corneas are tetrapods and legs may not have the heart has two atria and a ventricle except for the crocodiles that have two perfectly separate ventricles are oviparous with rich amniotic egg yolk and shell hard to avoid dryness are ectothermic the orders are more inportante quelonis ((turtle), crocodile, scaly (shed skin) birds: their body is shaped to accommodate the use flight feathers and the utensils for the limbs are formed by wings your mouth presents a peak lungs and air sacs have two atria and ventricles are sexual dimorphism and are homeothermic mammals migrate: they are divided into Cavez body, body and tail with cutaneous and mammary glands are two pairs of extrmidades with quiridio (5 fingers) have a nervous system are homeotherms and are viviparous (majority