Nucleus: Controls the activities of the cell and contains DNA.
Cell membrane: Controls what enters and leaves the cell.
Cytoplasm: Jelly-like substance where cell activities happen.
Mitochondria: Produces energy for the cell.
Ribosomes: Make proteins needed by the cell.
Vacuole: Stores water, nutrients, and waste.
The human body contains trillions of cells.
Cells can reproduce through cell division.
DNA contains instructions that tell cells how to function.
Different cells have different jobs, such as nerve cells sending messages and red blood cells carrying oxygen.
Mitochondria are called the “powerhouse of the cell” because they produce energy.
Cells need nutrients and oxygen to survive.
Cell Division
Cell division is the process where one cell creates new cells.
It helps organisms grow and repair damaged tissues.
Humans use a process called mitosis to create identical cells.
Cell division is important for replacing old cells.
Some cells in your body can repair themselves after damage.
Your body replaces billions of cells every day.
Red blood cells do not have a nucleus when they are mature, allowing more space for oxygen-carrying hemoglobin.
Nerve cells can be extremely long; some stretch from the spinal cord to the toes.
Some cells can “eat” harmful bacteria by surrounding and breaking them down.
Cells have tiny structures called organelles that work like organs inside the cell.
Mitochondria have their own small amount of DNA, separate from the DNA in the nucleus.
Cells can sense changes in their environment and respond to signals.
Some cells can store memories of past infections to help the immune system respond faster.
Cancer happens when cells lose control over their growth and divide too much.
Cells use a process called cellular respiration to turn nutrients into usable energy.
Cells can switch certain genes on or off depending on what they need to do.
Stem cells are special cells that can develop into many different types of cells.
Scientists use stem cells to study diseases and research possible treatments.
The study of cells is called cell biology or cytology.
Some viruses can enter cells and use the cell’s machinery to make more viruses.
Cells have a “quality control” system that checks and removes damaged parts.
Even though cells are tiny, they contain complex systems that work together like a miniature living machine.
MATH
if a number is - or + it becomes the opposite on the oppostie sdie of the = sign
Geometry Formulas:
Area Formulas
Square:
A = side × side
(A = s²)
Rectangle:
A = length × width
(A = l × w)
Triangle:
A = ½ × base × height
(A = ½bh)
Parallelogram:
A = base × height
(A = bh)
Trapezoid:
A = ½ × (base₁ + base₂) × height
(A = ½(b₁ + b₂)h)
Circle:
A = π × radius²
(A = πr²)
Perimeter / Circumference
Square:
P = 4 × side
(P = 4s)
Rectangle:
P = 2(length + width)
(P = 2l + 2w)
Triangle:
P = side₁ + side₂ + side₃
Circle (Circumference):
C = 2πr
or
C = πd
Volume Formulas
Cube:
V = side³
(V = s³)
Rectangular Prism:
V = length × width × height
(V = lwh)
Cylinder:
V = πr²h
Sphere:
V = ⁴⁄₃πr³
Cone:
V = ⅓πr²h
Other Important Geometry Formulas
Pythagorean Theorem (right triangles):
a² + b² = c²
(c is the longest side)
Distance Formula:
d = √((x₂ − x₁)² + (y₂ − y₁)²)
Slope Formula:
m = (y₂ − y₁) / (x₂ − x₁)
Sum of angles in a triangle:
180°
Sum of angles in a quadrilateral:
360°
Interior angle sum of a polygon:
(n − 2) × 180°
(n = number of sides)Geometry Formulas:
Area Formulas
Square:
A = side × side
(A = s²)
Rectangle:
A = length × width
(A = l × w)
Triangle:
A = ½ × base × height
(A = ½bh)
Parallelogram:
A = base × height
(A = bh)
Trapezoid:
A = ½ × (base₁ + base₂) × height
(A = ½(b₁ + b₂)h)
Circle:
A = π × radius²
(A = πr²)
Perimeter / Circumference
Square:
P = 4 × side
(P = 4s)
Rectangle:
P = 2(length + width)
(P = 2l + 2w)
Triangle:
P = side₁ + side₂ + side₃
Circle (Circumference):
C = 2πr
or
C = πd
Volume Formulas
Cube:
V = side³
(V = s³)
Rectangular Prism:
V = length × width × height
(V = lwh)
Cylinder:
V = πr²h
Sphere:
V = ⁴⁄₃πr³
Cone:
V = ⅓πr²h
Other Important Geometry Formulas
Pythagorean Theorem (right triangles):
a² + b² = c²
(c is the longest side)
Distance Formula:
d = √((x₂ − x₁)² + (y₂ − y₁)²)
Slope Formula:
m = (y₂ − y₁) / (x₂ − x₁)
Sum of angles in a triangle:
180°
Sum of angles in a quadrilateral:
360°
Interior angle sum of a polygon:
(n − 2) × 180°
(n = number of sides) these are all the ones ive learned and know well A=area
i heard most people stuggle with fractions, and i did too but i think these helped me a lot
Adding Fractions:
If the denominators are the same, add the numerators and keep the denominator.
Example: 2/5 + 1/5 = 3/5
If the denominators are different, find the least common denominator (LCD), make equivalent fractions, then add.
Subtracting Fractions:
If the denominators are the same, subtract the numerators and keep the denominator.
Example: 4/7 − 2/7 = 2/7
If the denominators are different, find the LCD, convert the fractions, then subtract.
Multiplying Fractions:
Multiply the numerators together and multiply the denominators together.
Formula: (a/b) × (c/d) = (a×c)/(b×d)
Example: 2/3 × 4/5 = 8/15
Dividing Fractions:
Use Keep, Change, Flip. Keep the first fraction, change division to multiplication, and flip the second fraction.
Formula: (a/b) ÷ (c/d) = (a/b) × (d/c)
Simplifying Fractions:
Divide the numerator and denominator by the same number until the fraction is in its simplest form.
Example: 8/12 = 2/3
Converting Mixed Numbers:
Multiply the whole number by the denominator, add the numerator, and place the answer over the denominator.
Example: 2 3/4 = 11/4
STUDY TIPS
i didnt put english beacuse it would be way too long but i think with voab there really is not much you can do, just memorizeas many words as you can AND READ READ READ i recommend (only if your REALLY committed to improving your engilsh grade, then buy a voab book or dictionary btw flash cards are useless, unless someone is pushing you to review and stuff
math is easy when you get it, i recommend if you have the standrd,to try kumon (ikikik its really bad) but it does help improve your grade if you think you nedd to improve
if your forced to go to someting like summer school, its okay cause theres peolpe who want to go summer school even if they dont have to
the more somebody forces you the more youll hate it, ik its kind of opposite of what i said before, but youll get it i promise