BIOL 1406 Lab Exam 1 Vocab

Random variable

observations that vary from one experiment to the next

Discrete random variable

random variable that can only be a whole number or integer

Continuous random variable

random variable that can be any positive number

Quantitative measurements

expressed with specific numbers and often units

Digital instrument

all figures shown are significant

Analog instrument

the significant figures include up to the first estimated digit

Graduated cylinders and pipettes

are accurate when used to measure volumes that are 50-100% of their capacity

Accuracy

describes how close a set of measurements is to a known or true value for the measurement (correctness)

Precision

how closes the measurements in a data set are to each other (consistency)

Mean

Sum of measured values/number of trials

Percent error

(|Mean-True value|/True value) x 100

Parallel dilution

usually done to make more than 1 dilution when the desired concentrations have no common dilution factor

C₁V₁=C₂V₂

Serial dilution

used to make several dilutions that share a common dilution factor or a single dilution that is too small to measure in lab

Dilution factor=(V₁+V₂)/V₁

Spectrometer

shines light on a sample and measures the amount of the light that has been absorbed by or passes through a sample

Independent variable

variable the scientists chooses to alter in an experiment

Dependent variable

variables that are measured in the experiment and are therefore dependent on the conditions of the experiment

Acid

H⁺ donor

when added to a solution, increases [H⁺]

Base

H⁺ acceptor

when added to a solution, increases [OH^-]

pH titration curve

a graph that shows the pH change of a solution as increasing amounts of acid or base are added

Buffering range

pH range in which a solution is effective at resisting pH changes

Buffering capacity

describes how well a solution can resist pH changes when additional acid or base is added

Qualitative measurement

Compound microscope

light from the object you are viewing passes through two lenses before it reaches your eye

Prokaryotic cell

no membrane bound organelles

plasma membrane and reinforced cell wall

flagella to move

includes bacteria and archaea

Eukaryotic cell

membrane bound organelles

larger and more complex

includes plants, fungi, protists

Plant cells

What eukaryotic cell is this?

• multicellular

• cell wall

• phototrophs

• make food

Protists

What eukaryotic cell is this?

• unicellular and multicellular

• amoebas and kelp

• phototrophs and heterotrophs

• flagella to move

Animal cells

What eukaryotic cell is this?

• multicellular

• heterotrophs

• consume and digest

Unicellular

made of 1 cell

Multicellular

consist of more than 1 cell

Colonial

organize into groups, can separate and form their own groups

Cell wall

adds structural support and protection to the cell

Plasma membrane

directs what goes in and out of the cell while maintaining its environment within the cell

Cytosol

water soluble fluid of the cell allowing movement of nutrients within the cell

Nucleus

encloses and protects the DNA within it

DNA

genetic material that directs the function of the cell and how to synthesize proteins

Ribosomes

use instructions read from RNA to build proteins

Rough endoplasmic reticulum

modify and aid in the folding of protein

Smooth endoplasmic reticulum

breaks down carbohydrates and synthesizes lipids

Golgi apparatus

Packages proteins to prepare them for transport to the other organelles

Vacuoles

store water, nutrients, and waste products of the cell

Vesicles

transport molecules (proteins, ions, hormones, etc.) within the cell and serve as storage for waste

Lysosomes

break down ineffective organelles and waste products using hydrolytic enzymes

Mitochondria

make ATP through cellular respiration

Chloroplasts

perform photosynthesis to make food for plants and photosynthetic protists

Diffusion

net/overall movement of atoms or molecules as the result of constant random motion

Osmosis

term used to describe the diffusion of water across a membrane

Simple diffusion

diffusion that occurs without assistance

gases and sterioids - small nonpolar molecules

facilitated diffusion

assisted diffusion using protein channels or carriers by following concentration gradients

ions and small polar molecules (water,glucose)

Active transport

ATP-required transport of atoms or molecules against their concentration gradient

Factors affecting diffusion rate

1. Size

2. Temperature

3. Medium through which diffusion is occuring

Dialysis diffusion

This type of diffusion is only affected by size of molecules. Ions and small polar molecules can easily diffuse across.

Movement

refers to the constant random movement of atoms or molecules

Net movement

refers to the overall direction of atoms/molecules movement or diffusion

Isotonic solution

solute concentration surrounding cells is equal to solute concentration within the cells

• no net movement of water

Hypertonic solution

solution surrounding a cell has a higher solute concentration that the inside of the cell

• net movement of water out of the cell

• cell shrinks

Hypotonic solution

solution outside of a cell has a lower concentration of solutes than the inside of the cell

• net movement of water into the cell

• cell swells and bursts