Atomic Structure and Periodic Trends
This subatomic particle determines the identity of an element.
Proton
This type of bond forms when atoms share electrons.
Covalent bond
This organelle carries out photosynthesis.
This process produces genetically identical daughter cells.
Mitosis
Most ecosystems get their energy from this source.
Sun
An atom has the electronic configuration 1s^2, 2s^2 2p^6, 3s^2, 3p^1. Identify the element.
Aluminum
Water molecules stick to each other (cohesion) because of this intermolecular force.
Hydrogen bonding
Movement of water across a membrane is called this.
This molecule carries genetic instructions from DNA to the ribosome.
mRNA
This is the process whereby all living things obtain energy.
Respiration
As you move across a period from left to right, atomic radius generally does this.
Decreases
Increasing concentration speeds up a chemical reaction because particles do this more often.
Collide
This type of transport requires ATP.
Active transport
A change in DNA sequence is called this.
Mutation
This process allows organisms to maintain stable internal conditions.
Homeostasis
An atom with 11 electrons will most likely form this ion charge.
+1
A reaction absorbs energy from its surroundings. This type of reaction is called this.
Endothermic
Name one structure found in plant cells but not animal cells.
Cell wall, chloroplast, large central vacoule
Two heterozygous parents are crossed. Predict the probability of a homozygous recessive offspring.
25%
These reactions release energy to the surroundings.
Exothermic reactions
Explain why potassium is more reactive than lithium.
Potassium’s valence electron is farther from the nucleus so doesn't feel the nuclear pull as much and so are easier to remove.
Explain why some molecules are polar while others are nonpolar.
Molecules are polar or nonpolar because of differences in electronegativity and the arrangement of atoms in the molecule. When atoms with different electronegativities bond, electrons are shared unequally, creating partial charges. If these unequal charges are distributed unevenly in the molecule, the molecule is polar. If electrons are shared equally, or if the molecule is symmetrical so the charges cancel out, the molecule is nonpolar.
Explain why large cells are less efficient at transporting materials than smaller cells.
Large cells have a lower surface area to volume ratio.
Explain how a mutation in DNA could eventually change the shape of a protein.
The mutation changes mRNA codons, which can change the amino acid sequence and protein folding.
A student leaves a sports drink in a hot car. Explain how heat could affect the particles in the drink and describe TWO changes that might happen because of increased particle movement.
Particles gain kinetic energy and move faster. Possible changes include faster evaporation, increased diffusion, increased reaction rate, or expansion of the liquid/container.