sem 2 exam revision Flashcards
What is force?
A force is an action exerted on an object to change it’s state of rest or motion
What is an unbalanced force?
When forces ARE NOT equal, causing a change in motion
What is a balanced force?
When forces ARE equal, causing no change in motion
What are free body diagrams?
A free body diagram is a simple sketch showing all the forces acting on an object
What is Newton’s First Law of Motion
An object at rest will remain at rest unless acted upon by an unbalanced force. An object in motion will continue at a constant speed and direction unless acted upon by an unbalanced force.
What is inertia?
Inertia is the tendency for an object to resist any change in motion
What is inertia’s relationship with mass?
The greater the mass, the greater the inertia
What is friction
Friction is a force that resists the motion of one object over another
What is air restistance?
A type of friction between air and another material
What is Newton’s Second Law of Motion
F = m x a
What is acceleration’s relationship with mass?
Acceleration of an object decreases with increased mass
Kg measures…
Mass
Newtons measure…
Force
m/s/s measures…
Acceleration
1N is equal to…
The force required to give a mass of 1kg and an acceleration of 1m/s/s
The acceleration due to gravity is…
9.8m/s/s
What is Newton’s Third Law of Motion?
For every action there is an equal and opposite reaction force
Name the forces acting on an aeroplane.
Lift (Force upwards), Weight (Force downwards), Drag (Force Right), Thrust (Force Left)
What is meiosis?
Meiosis is a type of cell division that produces gametes (sex cells)
How many daughter cells does the process of meiosis produce?
Meiosis produced 4 haploid daughter cells
Name the stages of meiosis
(IPMATPMAT)
Interphase, Metaphase I, Anaphase I, Telophase I, Prophase II, Metaphase II, Anaphase II, Telophase II
Describe interphase
Chromosomes prepare for cell division. They replicate but are NOT visible.
Describe prophase I
Chromosomes pair up and become visible.
Describe metaphase I
Chromosomes line up at the equator of the cell (M for middle)
Describe anaphase I
Chromosomes are pulled apart towards the centrioles (A for away)
Describe telophase I
The cell pinches in the center and divides.
Describe prophase II
2 diploid daughter cells are formed and visible
Describe metaphase II
Chromosomes line up at the equator
Describe anaphase II
Sister chromatids are pulled apart
Describe telophase II
Cell pinches in the center and divides. 4 haploid daughter cells are produced
What are homozygous alleles?
Homozygous alleles have 3 copies of the SAME allele, inheriting the same allele from each parent
What are heterozygous alleles?
Heterozygous alleles have 2 DIFFERENT alleles; inheriting a different allele from each parent
What is a dominant trait?
A dominant trait can be expressed with both homozygous and heterozygous alleles
What is a recessive trait?
A recessive trait can only be expression with homozygous alleles