ch 1 + 2 + 3 cards

an example of the organism level of biological organization is a

human

a population is a group of organisms of different species living in the same area.

false; this a community

steps in the Scientific Method?

1: make an observation

2: form a hypothesis

3: conduct an experiment

4: analyze the results

5: draw a conclusion

applying the scientific method involves designing an experiment to:

test a hypothesis

what is the difference between a dependent and an independent variable?

iv: what is being tested / manipulated
dv: measured for results

the independent variable is the variable that is

deliberately changed/manipulated

The scientific method is unlimited and can explain every phenomenon.

false, it has its limits, such as personal feelings

how did observations of orchids and moths confirm a prediction of evolutionary theory?

coevolution of specific traits

natural selection is the process by which organisms with advantageous traits:

survive

what is meant by “survival of the fittest”?

ability to reproduce

what is the structure of an atom?

nucleus (protons + neutrons) with orbiting electrons

An atom is composed of subatomic particles called:

protons, neutrons, and electrons

the reactivity of an atom is determined by its:

subatomic particles (protons, neutrons, and electrons)

what is a molecule?

two or more atoms bonded

bulk elements are required in ___ quantities, while trace elements are needed in ___

large ; small

ionic bond?

transfer of electrons

covalent bond?

sharing of electrons

hydrogen bond?

attraction between polar molecules

what is a polar molecule?

unequal distribution of electrons (such as water, oxygen atom has a partial negative charge, the two hydrogen atoms have partial positive charges)

the pH scale measures the concentration of ____ ions in a solution.

hydrogen

what is a buffer?

substance that resists pH change ; a neutralizer

dehydration synthesis removes a ___ molecule to form a bond between monomers

water

what is the structure of carbohydrates?

carbon, hydrogen, oxygen

what is a monomer?

one molecule (amino acids, nucleotides)

what is a polymer?

many molecules (DNA, synthetic fibers)

what are polysaccharides?

many simple sugars (starchy foods, potatoes & rice)

what are monosaccharides?

one simple sugar (glucose, fructose)

what does starch assist to?

energy storage in plants

cellulose is involved with what components?

structural component in plants

how many amino acids are there?

20

T or F: denatured protein retains its original structure.

false, cannot preform function

what are nucleotides?

building blocks of nucleic acids

there are five nitrogenous bases:

adenine, guanine, cytosine, thymine, and uracil.

what are the properties of a cell?

variable, adaptable, dynamic ((a cell can change when it needs to (variable), adjust to its environment (adaptable), and is always busy with movement and activity inside (dynamic))

different types of microscopes contribute to understanding:

cell structure

microscope types:

light microscope – lets you see whole cells and tissues, even alive

TEM (transmission electron microscope) – shows super-detailed insides of cells

SEM (scanning electron microscope) – shows 3D details of the cell’s surface

lipids are hydrophobic molecules.

meaning: they are scared of water

the cell theory includes the concept that all living organisms are:

composed of cells

what is the difference between saturated and unsaturated fats?

saturated fats have no double bonds

a peptide bond forms between two ___

amino acids

What components are common to all cells?

DNA, cytoplasm, ribosomes

The three domains of life are characterized by differences in their ___

cells, such as eukary prokary archea

the chemical structure of phospholipids enables them to form a:

bilayer in water (phospholipids have a water-loving head and water-fearing tails, so in water they line up tails together and heads out, making a double layer.)

why does a biological membrane have selective permeability?

to regulate molecule transport

Membrane proteins have various functions, including transport and ___

signaling

Organelles interact to carry out the ____

cell's functions

what is the primary function of cytoskeletal proteins?

to maintain cell structure

tight junctions seal cells so nothing leaks, desmosomes hold cells together like rivets, and gap junctions make tiny tunnels so cells can share signals and small molecules

.

animal cell junctions include tight junctions, gap junctions, and ___

desmosomes