bio exam 1

atom

the smallest unit of an element that maintains the properties of that element

ion

same atom with different charge. Atom that acquired or lost an electron or multiple electrons.

isotope

same with with different mass. Atom that acquired or lost a neutron or multiple neutrons.

"star stuff"

all atoms that make up life came from the big bang according to law of conservation of mass

covalent bond

atoms share electrons (strongest bond)

non polar covalent bond

equal sharing of electrons

polar covalent bond

unequal sharing of electrons

ionic bonds

one atom transfers electrons (moderate bond)

hydrogen bond

weak attraction between a hydrogen atom and another atom

cell theory

idea that all living things are composed of cells, cells are the basic units of structure and function in living things, and new cells are produced from existing cells

Cell

1-contained within a membrane
2-has genetic material
3-contains metabolic enzymes
4-capable of replication

Prokaryotic vs. Eukaryotic

Eukaryotic cells have nucleus and membrane bound organelles. Prokaryotic cells (BACTERIA) are unorganized and don't have a nucleus

What plant cells have that animal cells don't

cell wall, chloroplast, central vacuole

cell membrane

made of phospholipids-fatty acid tail and phosphate head group
is a fluid mosaic structure

cell membrane function

keeps things inside or outside; provides for communication via receptor proteins; controls what goes in and out of cell

diffusion

Movement of molecules from an area of higher concentration to an area of lower concentration

Osmosis

diffusion from low to high concentration

simple diffusion

lipid-soluble molecules move freely through membrane

facilitated diffusion

molecules move through channel proteins or carrier proteins

passive transport

no energy required

active transport

energy required

Cytoskeleton

structural framework of the cell

smooth ER

glycogen and lipid synthesis, chemical detoxification

rough ER

protein synthesis

ribosome

Makes proteins- reads directions from nucleus

Golgi apparatus

refines, packages, and ships products

nucleus

Control center of the cell- contains DNA

Nucleolus

Makes ribosomes

membrane

allow certain things in and out of cell- molecules have to have a tag to be allowed through the pore

vesicles

sends products to where they function

Peroxisomes

breaks down fatty acids and alcohols

lysosome

breaks down bacteria and worn out organelles

How does a cell make proteins?

1- signal goes to nucleus
2-blueprint copies itself and sends to ER
3-ribosomes uses instructions to make the protein
4-golgi apparatus packages and sends off through transport vesicle
5- goes out through exocytosis

inter vs intra molecular forces

intra-within a molecule inter-between molecules

metabolism

the sum of all chemical processes that occur in an organism

cellular respiration

the process by which cells use oxygen to produce energy from food

biochemical reactions

Chemical reactions that take place inside the cells of living things.

substrates

molecule that will be changed/broken

enzyme

changes the substrate

active site

a region on an enzyme that binds to substrate during a reaction.

endergonic

requires energy

exergonic

releases energy

ATP

energy currency of the cell

first step of aerobic respiration of glucose

glycolysis: 1 glucose to 2 pyrovate molecules; rips glucose in half through 10 enzyme steps

second step of respiration of glucose

prep step: pyrovate is shuttled from cytosol to mitochondria; pyrovate transferred to acetyl-COA; CO2 produced

third step of respiration of glucose

citric acid cycle: charges electron carriers; makes a pool of hydrogen ions which takes hydrogen atoms and energy

fourth step of respiration of glucose

electron transport chain: takes hydrogens from electron carriers and moves them to chain embedded in membrane; active transport of H+ against concentration gradient

fifth step of respiration of glucose

ATP Synthase: opens a channel for hydrogen ions to pass through intermembrane back into matrix

why use oxygen in ATP?

oxygen bonds to extra electron and H2 to form H2O

How do you know if a covalent bond between two atoms is polar or nonpolar?

One of the atoms is more electronegative than the other in the molecule and hogs electrons in the electron cloud. There is a +/- sign noted on the drawing of the molecule Whether or not it dissolves in water The molecule has a partial charge

what is the difference between an ionic and hydrogen bond?

Ionic bond is intramolecular (within molecule); Hydrogen bonds are intermolecular (between molecules). In an ionic bond an atom either loses or gains an electron, in a hydrogen bond you have attraction between partial charges of molecules.

An atom with an extra electron is called an

ion

What is a good question to ask to determine if a molecular bond is a polar covalent bond.

Are the electrons share equally? b. Does the molecule have a partial charge?

A nucleic acid monomer (nucleotide) has how many parts?

3 parts: a nitrogenous base, a sugar, and a phosphate group

Which part of an amino acid is responsible for the unique characteristics?

R-side-chain group

n Humans, carbohydrates are used for

Energy in the form of glycogen

Lipids (or fatty acids) are mainly made up of what 2 atoms?

carbon and hydrogen

water is

Universal Solvent, Sticky (to itself and other molecules/surfaces), high surface tension, solid state is less dense than liquid state, High specific heat.

how the polarity of water and polarity of salt facilitates salt dissolving in water

When a salt, like sodium chloride, is placed in water, the partially negative oxygen end of the water molecule is attracted to the positively charged sodium ion. The partially positive hydrogen end of the water molecule is attracted to the negatively charged chloride ion. These attractions cause the NaCl salt to break up and dissociate, or dissolve - the intramolecular ionic bond between the Na and Cl ions are replaced by intermolecular bonds with the water molecules.

Describe the location and steps a protein takes from synthesis to where it resides in the peroxisome, and what the function of the protein might be once it gets there.

Through the endomembrane system protein synthesis occurs.
In the nucleus, copies of genes are made and instructions are sent out from DNA blueprints.
In the endoplasmic reticulum, the proteins are synthesized. The ribosomes attached to the rough er assist in this process. The proteins are folded and given quality control, before they go to the smooth er.
There, the proteins are modified before being collected from the Golgi apparatus.
The Golgi body takes those proteins and modifies and packages and puts them in vesicles for transport.
When the vesicles detach, it becomes a peroxisome. Some proteins stay within the cell and some go to used outside of the cell. These proteins are sent to where they function in the cell and often get rid of waste.

diffusion in your own words. What is different about osmosis

Diffusion is the passive, natural movement of a molecule (solute) from an area of high concentration to an area of low concentration until the concentration of the solute is the same throughout the solution. Osmosis is similar, only the solvent moves to an area of high solute concentration in an attempt to equalize concentration because the solute cannot pass through a semipermeable membrane.

protein

A three dimensional polymer made of monomers of amino acids. Enzymes, receptors, hormones, signaling molecules, channels, etc.

lipids

Fatty acid tails made out of hydrogens and carbons. HYDROPHOBIC & NON-POLAR. Doesn't mix with water. Shares electrons equally between atoms.

carbs

Monomer sugar Polymer polysaccaride. form very long chains. Can be linear or branched. structure, energy storage.

nucleic acid

ATP \= nucleotide monomer \= energy currency of the cell. Store information, act as enzymes, used as energy currency. Monomer nucleotide \= phosphate + nitrogenous base + sugar. Form into a double helix molecules with a sugar backbone. Nitrogenous bases hold the information.

cell types has a nucleus

animal and plant

cell type has DNA

prokaryote and eukaryote

Which part of the phospholipid is facing the inside of the cell?

head

What strategy is used for very large macromolecules that need to move from the extracellular space to the intracellular space?

endocytosis

moves molecules from low solute to high solute concentration?

active transport

Identify the differences between Prokaryotic and Eukaryotic cells.

Which one has a nucleus? Eukaryotes
Which one lacks most cell organelles? Prokaryotes
Which one is larger on average? Eukaryotes
Which type do humans have? Eukaryotes
Which type contains DNA? Both

features do plant cells have that animal cells lack

Large central vacuole that fills with water, cell wall for rigid structural support, chloroplasts for energy harvesting.

3 components that make up a cell membrane and their function:

Lipids Phospholipid bilayer + Cholesterol; Make up a majority of the cell membrane. Give characteristic of selective permeability and barrier function. Cholesterol maintains fluidity of membrane. Protein signal receptors, transporters, channels, pores, anchors. Allow some things to pass through that cannot get past lipid bilayer. Facilitate cell signaling. Carbohydrates cell markers and identifiers.

Diffusion

The molecules move directly through/across the lipid bilayer from high solute concentration to low solute concentration.

small, nonpolar molecules (oxygen, carbon dioxide, lipid-based hormones)

facilitated diffusion

The molecules move through channel proteins embedded in the lipid bilayer, moving from high solute concentration to low solute concentration.

larger and/or polar molecules (glucose)

facilitated and dissusion bth

go high to low

Active transport

low to high, require energy, channel protein

facilitated Diffusion

high to low, channel protein

fates of a vesicle that buds off from the Golgi bodies/apparatus?

Exocytosed, (2) packed into a vesicle and shipped to other organelles where they function, (3) packed into a vesicle that will become a lysosome, (4) packed into a vesicle that will become a peroxisome.

What structural element of the endomembrane system facilitates constant communication and flux between the organelles in the system?

Phospholipid bilayer surrounding each organelle

Which organelle packages and sends proteins to where they function in the cell (like a post office sorting mail)?

Golgi apparatus

Cells are able to join together to build the tissues that make up an organism because

Proteins in the plasma membrane join cells together

we are

eukaryotic

simple to complex

atom, molecule, macromolecule, organelle, cell, tissue

polar

0.4- 0

nonpolar

0.4-1.8

ionic

1.8+

solute

A substance that is dissolved in a solution. h to low

solvent

the substance in which the solute dissolves. low to high

intermolecular bonds

bonds between molecules

intramolecular bond

A bond which occurs between atoms within molecules

Polymerization

joining monomers to form a polymer

monomer

small chemical unit that makes up a polymer

polymer

A long molecule consisting of many similar or identical monomers linked together.

Hydrolysis

A chemical process that splits a polymer by adding water.

dehydration reaction

A chemical reaction in which molecules combine by removing water

monomer

sugar, nucleotide

polymer

carbohydrate, nucleic acid

prokaryote

A unicellular organism that lacks a nucleus and membrane bound organelles
most comon
smaller
dna not in chromesomal form
nucleic

Eukaryote

A cell that contains a nucleus and membrane bound organelles
larger
dna in chromsomsal form
membrane boud compartments