BIO 122 exam 1

atmosphere of hydrogen and helium..

blown off by solar winds

sterols

can be structural or act as hormones

Correlation doesn't equal...

causation

amino acids

class of small molecule that're the building blocks of proteins

lipids are partly....

hydrophobic

steps of scientific method

1- make observations 2- think of interesting quest. 3- formulate hypothesis 4- develop stable predictions 5- gather data to test predictions 6-refine, alter, expand or reject hypothesis 7- develop general theories

molecule

2 or more elements connected by covalent bonds

biomolecules

4 main types are proteins, carbohydrates, nucleic acids and lipids all are critical for living cells all are built on a framework of covalently bonded carbon atoms

carbon atoms have how many potential binding sites?

4 potential binding sites. They can therefore bind to 4 different atoms

lipids

4th category of biomolecules, better known as fats oils and steroids

what percent of our bodies is water?

50-60%

What percent of Earth is water?

70%

What percent of a cell is water?

70-75%

are lipids polymers?

NO, lipids are macromolecules because their structure isn't composed of a chain of monomers

scientific theory

a hypothesis, or a group of related hypothesis, that has been repeatedly confirmed by diverse independent researchers

hydrogen bond

a weak electrical attraction between a partially positive hydrogen atom and a partially negative end of a polar molecule

control

allows for comparisons w/ treatments

scientific hypothesis

an informed logical and plausible explanation for observations of natural world statement not a question

hydrogen bonds are constantly bonding...

and breaking

Atomic mass number

approximately how much an atom weighs (the combined number of protons and neutrons in an atoms nucleus)

inorganic molecules

aren't covalently bound to other carbon or hydrogen atoms

covalent bonds

atoms share electons

experiments in lab

can control settings and have replicates nature=more things happening

the central element found in organic molecules is...

carbon

what type of reactions release energy by breaking down complex molecules?

catabolic

plants

cellulose~~ cellulose fibers starch~~ starch grain

non plants

chitin glycogen

experiments in whole ecosystems

closest you can get to a real natural setting hard to replicate-sometimes only one high cost, manipulating environment

triglycerides

composed of 3 fatty acid molecules linked to a glycerol molecule provide long-term energy storage in both plants (as oils) and animals (as fats) and serve as insulation against the cold in animals

steroids

composed of hydrocarbon rings and fatty acids are hormones and cholesterol

phospholipids

composed of phosphate group, glycerol and 2 fatty acids have a hydrophilic (polar) head and a hydrophobic (nonpolar) tail

carbon can form multiple...

covalent bonds

which of the following statements is true of proteins, carbohydrates, and nucleic acids?

each of these molecules is built from a common set of monomers

which of the following is a part of accepted cell theory...

every living organism is composed of one or more cells, and all living cells arise from preexisting cells.

ways to collect data

field observations

liquid water

formation of the oceans allowed for the stages of life to begin

organic molecules

have chains of carbon atoms covalently bound to other carbon and hydrogen atoms

in the phospholipid

heads get put together w/ tails on inside of cell wall

water is sticky (key functions of water that influence life)

hydrogen bonding allows water molecules to stick to one another (cohesion) and to other surfaces (adhesion), making them wet. example: capillary action

new meds undergo extensive human testing before receiving FDA approval. These tests represent an experiment, and variations in the dosage given to participants represents the...

independent variable

a scientific hypothesis must be constructed with which of the following characteristics?

it provides a reasonable explanation to a question and is consistent with current observations; it must also be testable and falsifiable

Water is called the universal solvent because...

it successfully dissolves so many substances

LUCA

last universal common ancestor

which of the following macromolecules is not made of monomers

lipid

fatty acids

lipids have different characteristics based on how their carbon molecules are bound a) a saturated fatty acid, stearic acid (straight chain) b) an unsaturated fatty acid, oleic acid

early earth was...

liquid magma with no atmosphere

polymers

long strands of repeating units of small molecules called monomers proteins, carbohydrates, and nuclei acids are polymers lipids are not polymers bc. their structure is not composed of a chain of monomers

a solid waste (garbage) transfer facility that sorts and breaks down garbage into recyclables and waste to be thrown away in the landfill would be a suitable analogy for which cellular organelle

lysosome

Nucleus

made of closely bound protons and neutrons

why are water molecules spaced further apart in an ice crystal?

makes ice less dense than water and able to float on it

prokaryotes and eukaryotes are primarily distinguished by the absence or presence of internal...

membrane-enclosed organelles

human muscle cells need large amounts of ATP to function in the movement of the body, which is why__________ are especially abundant in muscle cells

mitochondria

chemical compounds

molecules w/ atoms from 2 or more different elements

Experiments in the field

more real to the real world setting still can control and have replicates

electrons

negatively charged particles surrounding the nucleus

no core =...

no gravity

atomic number

number of protons in an atoms nucleus (unique to each element)

solid = ice

occurs at and below 0 degrees Celsius stable network of hydrogen bonds emerges as a crystal structure

liquid = fluid water

occurs at between 0 and 100 degrees celsius water bonds constantly break and reform

gas = water vapor or steam

occurs when water boils at 100 degrees celsius

cell theory

one of the unifying principles of biology consists of 2 main parts every living organism

carbon forms what kind of molecules?

organic and inorganic molecules organic: glucose and inorganic: carbon dioxide

the reliability of primary scientific literature is strengthened by the ____________ process, in which the work is examined by other leaders in the same field.

peer-review

what is the main component of cellular membranes?

phospholipids

living cells have an intact phospholipid layer that separates the cell from its external environment; this structure is commonly referred to as the..

plasma membrane

DNA (deoxyribonucleic acid)

polymer of deoxyribonucleotide monomers provides living organisms long term , stable genetic info

RNA (ribonucleic acid)

polymer of ribonucleotide monomers many forms and plays many role, most important job is providing a readable genetic language that enables genes to be expressed as proteins

proteins

polymers of the 20 amino acid monomers are the most numerous and versatile of the 4 bio molecules vary in size and shape and therefore function

independent variable

predictor variable -treatments -gradient in natural world

eleent

pure substance that has distinctive physical and chemical properties, and that cannot be broken down

scientific fact

repeatable observation of natural world -may change as observations become more accurate

during exercise, the increase in respiration rate and heart rate are driven by the need to replenish the oxygen used to support

respiration in muscle cell mitochondria

dependent variable

response variable

experiments in medicine

series of steps has to go through before it reaches the public test on rats and other animals then humans 3 phases

covalent bond atoms...

share electrons

what do lipids vary in?

size, shape and therefore function

cells

smallest most basic unit of life microscopic, self contained units enclosed by a protective membrane

atom

smallest unit of an element that retains its distinctive properties

scientific claim

statement about how the world works that can be tested using the scientific method

photosynthetic organisms capture energy from sunlight and convert it into chemical bonds by forming

sugars

what is made during photosynthesis that is transported around the plant to provide fuel for respiration

sugars

water can absorb a lot of energy (key functions of water that influence life)

takes a lot of heat energy to disrupt the strong hydrogen bonds between water molecules. That is why water is a liquid at a wide range of temperatures ex- hold heat=sweating life can exist on most of earth

a hypothesis must make predictions that are...

testable falsifiable or refutable supported, but never proven precise example:"if...then" statement

nucleic acids

the 3rd most crucial category of polymers 2 types form the basis of life itself, DNA and RNA

earth cooled and...

the core (gravity) and water formed

Sugars

the monomers of carbohydrates a) hexoses: glucose, fructose, calatctose b) pentoses: deoxyribose, ribose

carbohydrates

the next-most-versatile biomolecules are simple monomer sugars and polymers of simple sugars

states of matter for water

the physical state of water depends on temperature solid=ice liquid=fluid water gas= water vapor or steam

Biology

the study of living organisms

the earth is referred to as..

the water planet

the function of all macromolecules is most determined by...

their size and stucture

different combos of deoxyribonucleotide monomers in a DNA polymer or different combos of ribonucleotide monomers in RNA polymer allow them...

to perform different functions

water is a...

universal solvent, example: coffee

RNA and DNA both...

vary in size and shape and therefore function

in living systems, a critical component of many reactions is...

water

hydrophobic

water-fearing-uncharged, non-polar molecules ex: oil

hydrophilic

water-loving "like dissolves like" ex: vinegar

polar molecules

when electrons are unequally shared between atoms, partial electrical charges result w/in a molecule

Ice is less dense than liquid water

when water freezes, bonds between the water molecules become rigid and expand, increasing the overall volume of the water this makes ice less dense than liquid water. why ice floats, reason why life survives in water.

what does water molecules form hydrogen bonds with?

with other polar molecules, like sugar and salt