Lab Review

Question 1

what is the scientific method

Answer 1

a method of procedure that has characterized natural science since the 17th century, consisting in systematic observation, measurement, and experiment, and the formulation, testing, and modification of hypotheses.

Question 2

steps of the scientific method

Answer 2

1. Make an observation.
2. Ask a question.
3. Form a hypothesis, or testable explanation.
4. Make a prediction based on the hypothesis.
5. Test the prediction.
6. Iterate: use the results to make new hypotheses or predictions.

Question 3

what is a hypothesis

Answer 3

a supposition or proposed explanation made on the basis of limited evidence as a starting point for further investigation.

Question 4

comparative vs controlled experiments

Answer 4

comparative = Involves collecting data on different populations/organisms under different conditions (ex. Times of year, Locations), to make a comparison.

controlled = an experiment in which all the variable factors in an experimental group and a comparison control group are kept the same except for one variable factor in the experimental group that is changed or altered

Question 5

independent vs dependent vs standardized variables

Answer 5

independent = a variable (often denoted by x ) whose variation does not depend on that of another.

dependent = a variable (often denoted by y ) whose value depends on that of another.

standardized = a variable that has been rescaled to have a mean of zero and a standard deviation of one

Question 6

conversion of m and nm

Answer 6

1m=100cm 10^2
1000mm 10^3
1000000um 10^6
1000000000nm 10^9

Question 7

what are are the four major macromolecules

Answer 7

lipids, carbohydrates, proteins, and nucleic acids

Question 8

what is osmosis

Answer 8

a process by which molecules of a solvent tend to pass through a semipermeable membrane from a less concentrated solution into a more concentrated one

Question 9

hypertonic means

Answer 9

a solution has a higher concentration of solute than is found in the cells and the water leaves the cell

Question 10

hypotonic means

Answer 10

a solution has a lower solute concentration than the cells and the cells take up water

Question 11

isotonic means

Answer 11

an extracellular solution which contains the same concentration as the solute

Question 12

what happens to a cell in a hypertonic solution

Answer 12

in plant and animal the cells shrink

Question 13

what happens to a cell in a hypotonic solution

Answer 13

in plant they swell and increase turgor pressure and in animal they burst

Question 14

what happens to a cell in a isotonic solution

Answer 14

nothing

Question 15

what is ATP

Answer 15

the immediate energy source for most of a cells activities

Question 16

what is potential energy in a cell

Answer 16

the energy stored in bonds of the. molecule

Question 17

number of carbons in glucose and fructose

Answer 17

6

Question 18

number of carbons in sucrose

Answer 18

12

Question 19

why do we make yeast and water a control when comparing different carbohydrates

Answer 19

because water does not have any sugar/ carbon in it which yeast needs to grow

Question 20

what part of a phospholipid is hydrophilic

Answer 20

the phosphate group head

Question 21

what part of a phospholipid is hydrophobic

Answer 21

the fatty acid tail

Question 22

how does a spec work

Answer 22

it measures the absorbance

Question 23

what is an enzyme

Answer 23

a catalyst that speeds up chemical reaction without being used in up in the process

Question 24

what is a catalyst

Answer 24

they are very specific and they react with a certain substrate to catalyze a narrow class of chemical reactions

Question 25

what is hydrogen peroxide in our enzyme lab

Answer 25

the substrate for our enzyme

Question 26

what is photosynthesis

Answer 26

the process by which plants and certain algae synthesize simple organic molecules from carbon dioxide and water

Question 27

what is replication

Answer 27

the process of copying DNA to make new DNA

Question 28

what is translation

Answer 28

the final step to turn the DNA message into a protein product. The mRNA matches to anticodons on tRNA to bring specific amino acids based on the genetic code

Question 29

what is transcription

Answer 29

this occurs on a regular basis in every single cell if the body and this is the process of using the info stored in DNA to make mRNA

Question 30

why does starch have the most potential energy with yeast

Answer 30

it has repeating glucose units

Question 31

stains combine with what to increase contrast of cells under a microscope

Answer 31

low power, stage all the way up

Question 32

why is staining a step often used when looking at cells under a microscope

Answer 32

increases contrast

Question 33

when you begin to focus the microscope, which combination below is correct

Answer 33

low power, stage all the way up

Question 34

how do we obtain the major macromolecules our bodies need

Answer 34

common foods

Question 35

indicators can test for the presence of

Answer 35

sugars, fats, and proteins

Question 36

in diffusion substances move from a _______ concentration to a ________ concentration

Answer 36

higher, lower

Question 37

Biurets reagent is an indicator for the presence of

Answer 37

proteins

Question 38

Benedicts reagent is an indicator for the presence of

Answer 38

sugar

Question 39

if a cell crenates, it

Answer 39

shrinks

Question 40

why do we say that a 12 carbon sugar has more potential energy than a 6 carbon sugar

Answer 40

more carbons mean more energy and 12 carbons has more potential energy because not all organisms could break down the 12 C to release the energy

Question 41

what is the relationship between variance and standard deviation

Answer 41

take the square root of variance to get SD

Question 42

give the equation to calculate enzyme activity rate

Answer 42

final absorbance reading reading - initial absorbance reading / number of seconds

Question 43

what does an optimal pH give

Answer 43

the highest enzyme activity

Question 44

the function of peroxidase is to turn hydrogen peroxide into

Answer 44

water and oxygen

Question 45

photosynthesis uses carbon dioxide and water to make the final product

Answer 45

glucose

Question 46

why/ how does pH affect enzyme activity

Answer 46

alters structure and lowers activity

Question 47

why do leaf disks float in the solution contains sodium bicarbonate but not in the solution without sodium bicarbonate

Answer 47

bicarbonate is the carbon source - without it no photosynthesis, no oxygen, no floating

Question 48

photosynthesis produces oxygen. What is the process that consumes oxygen and produces ATP for the cell

Answer 48

cellular respiration

Question 49

what is the purpose of soap in the solutions for the leaf disk assay

Answer 49

wets the hydrophobic leaf surface allowing solution to get into the leaf

Question 50

stage of meiosis I in which the homologous pairs line up on the equilateral plate

Answer 50

metaphase I

Question 51

stage of meiosis in which the chromosomes gather into nuclei, and the original cell divides

Answer 51

telophase I

Question 52

stage of meiosis II in which the chromosomes gather into nuclei and the cells divide

Answer 52

telophase II

Question 53

stage of meiosis I in which the chromatin begin to condense following interphase

Answer 53

early prophase I

Question 54

stage of mitosis in which daughter chromosomes reach the poles, the nuclei re-form, and the cell again enters interphase

Answer 54

telophase

Question 55

where in the mouth are taste receptors located

Answer 55

taste buds

Question 56

papillae are visible to the naked eye

Answer 56

true