Name: verbal working memory with word lists
Uploaded: 2023-04-30T06:33:25.000Z
Duration: 6 min 44 s
Channel: JoVE

K12 Standards

new-york-state-science-learning-standards

New York State Science Learning Standards

High School

Life Science

Structure and Function

HS-LS1-2.

Measuring Verbal Working Memory Span

1. Make a set of word lists.
<ol>
	<li>To make stimuli for this experiment, gather 40 index cards and a pen.</li>
	<li>Generate a random list of 210 common nouns, words like, car, dog, pen, boat, chair, and hammer.</li>
	<li>Each index card will include three, four, five, six, seven, eight, or nine common nouns on it. Make five cards with each number. Don&#8217;t repeat nouns from list to list, and try not to have them group together by category. For example, avoid lists with only animals or tools or foods. Instead, try to make sure the lists are mixed, with a variety of content types on each. A sample list of three words might include bowl, table, and saw and a sample list for five might include: shelf, deer, jelly, book, and flame.</li>
</ol>
2. Test a participant.
<ol>
	<li>Place your index cards face down on a table between you and the participant, organized into piles for each number of words.</li>
	<li>Explain the instructions: On each trial, the experimenter will pick up one of the cards, slowly read the words on the card in order from top to bottom, and as soon as the experimenter finishes the participant will need to repeat the list, in the same order.</li>
	<li>Start with the top card on the three-word pile, complete that pile, and work your way up.</li>
	<li>As the participant responds note on the relevant card whether a word was repeated back correctly by placing a check mark next to a word when the participant says it, or an &#8216;X&#8217; if she fails to, or says something else in its place. The words need to be reported back in the right order. </li>
	<li>The experiment is done when you get through all the lists.</li>
</ol>
3. Perform the analysis.
<ol>
	<li>If you go back the index cards, you have a record of whether each word in a list was recalled correctly or not.</li>
	<li>The most informative way to analyze these results is in terms of the number of words in a list, and a given word&#8217;s position in a list. For all the cards with three words, for example, you can compute the probability that the first word was recalled correctly, and the same for the second and third words. Do this for all the lists, and input the results into a spreadsheet (Table 1).</li>
	<li>For graphing purposes, translate Table 1 into a more compact summary of accuracy as a function of word position and list length (Table 2).</li>
</ol>
<table border="1" cellpadding="0" cellspacing="0">
	<tbody>
		<tr>
			<td>List Length</td>
			<td>Word Position</td>
			<td>Number correct</td>
			<td>Percent Correct</td>
		</tr>
		<tr>
			<td>3</td>
			<td>1</td>
			<td>5</td>
			<td>100</td>
		</tr>
		<tr>
			<td>3</td>
			<td>2</td>
			<td>5</td>
			<td>100</td>
		</tr>
		<tr>
			<td>3</td>
			<td>3</td>
			<td>5</td>
			<td>100</td>
		</tr>
		<tr>
			<td>4</td>
			<td>1</td>
			<td>5</td>
			<td>100</td>
		</tr>
		<tr>
			<td>4</td>
			<td>2</td>
			<td>4</td>
			<td>80</td>
		</tr>
		<tr>
			<td>4</td>
			<td>3</td>
			<td>5</td>
			<td>100</td>
		</tr>
		<tr>
			<td>4</td>
			<td>4</td>
			<td>5</td>
			<td>100</td>
		</tr>
		<tr>
			<td>5</td>
			<td>1</td>
			<td>5</td>
			<td>100</td>
		</tr>
		<tr>
			<td>5</td>
			<td>2</td>
			<td>4</td>
			<td>80</td>
		</tr>
		<tr>
			<td>5</td>
			<td>3</td>
			<td>4</td>
			<td>80</td>
		</tr>
		<tr>
			<td>5</td>
			<td>4</td>
			<td>5</td>
			<td>100</td>
		</tr>
		<tr>
			<td>5</td>
			<td>5</td>
			<td>5</td>
			<td>100</td>
		</tr>
		<tr>
			<td>6</td>
			<td>1</td>
			<td>4</td>
			<td>80</td>
		</tr>
		<tr>
			<td>6</td>
			<td>2</td>
			<td>4</td>
			<td>80</td>
		</tr>
		<tr>
			<td>6</td>
			<td>3</td>
			<td>3</td>
			<td>60</td>
		</tr>
		<tr>
			<td>6</td>
			<td>4</td>
			<td>3</td>
			<td>60</td>
		</tr>
		<tr>
			<td>6</td>
			<td>5</td>
			<td>3</td>
			<td>60</td>
		</tr>
		<tr>
			<td>6</td>
			<td>6</td>
			<td>5</td>
			<td>100</td>
		</tr>
		<tr>
			<td>7</td>
			<td>1</td>
			<td>4</td>
			<td>80</td>
		</tr>
		<tr>
			<td>7</td>
			<td>2</td>
			<td>2</td>
			<td>40</td>
		</tr>
		<tr>
			<td>7</td>
			<td>3</td>
			<td>3</td>
			<td>60</td>
		</tr>
		<tr>
			<td>7</td>
			<td>4</td>
			<td>2</td>
			<td>40</td>
		</tr>
		<tr>
			<td>7</td>
			<td>5</td>
			<td>2</td>
			<td>40</td>
		</tr>
		<tr>
			<td>7</td>
			<td>6</td>
			<td>3</td>
			<td>60</td>
		</tr>
		<tr>
			<td>7</td>
			<td>7</td>
			<td>4</td>
			<td>80</td>
		</tr>
		<tr>
			<td>8</td>
			<td>1</td>
			<td>5</td>
			<td>100</td>
		</tr>
		<tr>
			<td>8</td>
			<td>2</td>
			<td>3</td>
			<td>60</td>
		</tr>
		<tr>
			<td>8</td>
			<td>3</td>
			<td>3</td>
			<td>60</td>
		</tr>
		<tr>
			<td>8</td>
			<td>4</td>
			<td>1</td>
			<td>20</td>
		</tr>
		<tr>
			<td>8</td>
			<td>5</td>
			<td>3</td>
			<td>60</td>
		</tr>
		<tr>
			<td>8</td>
			<td>6</td>
			<td>2</td>
			<td>40</td>
		</tr>
		<tr>
			<td>8</td>
			<td>7</td>
			<td>3</td>
			<td>60</td>
		</tr>
		<tr>
			<td>8</td>
			<td>8</td>
			<td>4</td>
			<td>80</td>
		</tr>
		<tr>
			<td>9</td>
			<td>1</td>
			<td>4</td>
			<td>80</td>
		</tr>
		<tr>
			<td>9</td>
			<td>2</td>
			<td>3</td>
			<td>60</td>
		</tr>
		<tr>
			<td>9</td>
			<td>3</td>
			<td>1</td>
			<td>20</td>
		</tr>
		<tr>
			<td>9</td>
			<td>4</td>
			<td>3</td>
			<td>60</td>
		</tr>
		<tr>
			<td>9</td>
			<td>5</td>
			<td>2</td>
			<td>40</td>
		</tr>
		<tr>
			<td>9</td>
			<td>6</td>
			<td>1</td>
			<td>20</td>
		</tr>
		<tr>
			<td>9</td>
			<td>7</td>
			<td>3</td>
			<td>60</td>
		</tr>
		<tr>
			<td>9</td>
			<td>8</td>
			<td>3</td>
			<td>60</td>
		</tr>
		<tr>
			<td>9</td>
			<td>9</td>
			<td>4</td>
			<td>80</td>
		</tr>
	</tbody>
</table>
Table 1. List learning results. Example data from one participant. Recall that there were five cards for each list length. For a given word position and given list length, the participant had five opportunities. Percentage correct is thus the number of correct responses out of five.
<table border="1" cellpadding="0" cellspacing="0">
	<tbody>
		<tr>
			<td></td>
			<td>Position</td>
			<td></td>
			<td></td>
			<td></td>
			<td></td>
			<td></td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Length</td>
			<td>1</td>
			<td>2</td>
			<td>3</td>
			<td>4</td>
			<td>5</td>
			<td>6</td>
			<td>7</td>
			<td>8</td>
			<td>9</td>
		</tr>
		<tr>
			<td>3</td>
			<td>100</td>
			<td>100</td>
			<td>100</td>
			<td></td>
			<td></td>
			<td></td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>4</td>
			<td>100</td>
			<td>80</td>
			<td>100</td>
			<td>100</td>
			<td></td>
			<td></td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>5</td>
			<td>100</td>
			<td>80</td>
			<td>80</td>
			<td>100</td>
			<td>100</td>
			<td></td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>6</td>
			<td>80</td>
			<td>80</td>
			<td>60</td>
			<td>60</td>
			<td>60</td>
			<td>100</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>7</td>
			<td>80</td>
			<td>40</td>
			<td>60</td>
			<td>40</td>
			<td>40</td>
			<td>60</td>
			<td>80</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>8</td>
			<td>100</td>
			<td>60</td>
			<td>60</td>
			<td>20</td>
			<td>60</td>
			<td>40</td>
			<td>60</td>
			<td>80</td>
			<td></td>
		</tr>
		<tr>
			<td>9</td>
			<td>80</td>
			<td>60</td>
			<td>20</td>
			<td>60</td>
			<td>40</td>
			<td>20</td>
			<td>60</td>
			<td>60</td>
			<td>80</td>
		</tr>
	</tbody>
</table>
Table 2. Summary of list learning results. The data are summarized in terms of response accuracy as a function of a word&#8217;s position in a list and the length of the list.
<div id="script_0" class="chapter_text">
	To actively remember information over a short duration, Individuals rely on a specialized memory system called working memory.
	Unlike long-term memory, working memory has a very limited capacity, which allows selective information to remain active-to be studied, manipulated, and then transferred to other memory and cognitive systems.
	Researchers can measure the capacity limit of verbal working memory-the memory span-through the use of a verbal list paradigm. This paradigm involves the researcher reading word lists of varied lengths to subjects and then asking the subjects to repeat back the words in sequential order.
	This video demonstrates standard procedures for studying verbal working memory span by explaining how to design and conduct the experiment, as well as how to analyze and interpret the results.
</div>
<div id="script_2" class="chapter_text">
	In this experiment, participants listen as an experimenter reads word lists with varying lengths. In this case, word positions among the varied-length lists are the independent variables. 
	Participants are then asked to hold words in working memory while a list is read, after which they are asked to recall the words on the list in the same order. Recall accuracy, or how many words on the list are repeated back in the correct order, is the dependent variable. 
	At the beginning of the list, words are mentally rehearsed more than those in latter positions. Therefore, higher recall accuracy is hypothesized for words in the primary positions. Such performance is referred to as a primacy effect.
	In contrast, when longer lists need to be recalled, contents of verbal working memory interfere with each other. Thus, the words in the middle of a list are recalled with greater difficulty, because they have more neighbors.
	Since words at the end of the list were heard most recently and have few interfering neighbors, they are expected to be recalled with high accuracy. This aspect of verbal working memory is referred to as the recency effect.
	Finally, verbal working memory span is classified by identifying the longest list for which participants performed better than 75% correct across all word positions.
</div>
<div id="script_3" class="chapter_text">
	To conduct this study, prepare stimuli by generating a random word list of 210 common nouns, such as car, dog, pen, or boat. 
	From the master list of nouns, create seven varied-length piles, each containing five index cards with different nouns written on each one. Thus, for the first stack, start by writing three of the generated nouns, and increase the number of words for each stack until you have a list length of nine. 
	To finalize the word lists, verify that no nouns are repeated across the lists or clustered into categories that would unintentionally make recall easier. Arrange the stacks into piles of increasing order-from shortest to longest-and place facedown. 
	To begin the experiment, greet the participant and have them take a seat facing you, with the pile of index cards placed in front of you. Explain the instructions to the participant, providing details on how they should remember the words read to them and then repeat the list back in the proper order.
	First, pick up a card and slowly read the words out loud in order from top to bottom. When you reach the end of the list, say 'Go.'
	As the participant recites the list back, follow along on the card and mark whether each word was repeated back correctly or incorrectly in the right order by placing a checkmark or X, respectively.
	Make sure to go through all cards in each pile before moving on to the next one. Complete the session with the longest list.
</div>
<div id="script_4" class="chapter_text">
	To analyze the data, tally the results based on the number of words and the position of each word in the list for all of cards in each set. Remember that there were five total responses for each position.
	To visualize list recall performance, plot percent correct as a function of word position by list length. Notice that recall is more accurate for words positioned in the beginning and end of the lists than the middle words, confirming the primacy and recency effects in verbal working memory.
	To calculate working memory span, summarize percent correct as a function of list length and word position. Identify the longest list for which a participant performed better than 75% correct for all word positions.
</div>
<div id="script_5" class="chapter_text">
	Now that you are familiar with designing a verbal list paradigm, you can apply this approach to answer specific questions about working memory function. 
	Working memory is engaged on a daily basis, for recalling detailed steps to a favorite recipe, or trying to remember the names of several new people at a social function.
	In addition, memory span is included as a component of many intelligence tests, as the measure correlates very reliably with IQ.
	Such correlations also allow memory span to be used with functional imaging to determine whether brain damage impacts cognitive functioning in general, or as an indicator for degenerative diseases such as Alzheimer's.
</div>
<div id="script_6" class="chapter_text">
	You've just watched JoVE's introduction on verbal working memory span. Now you should have a good understanding of how to design and conduct the experiment, as well as how to analyze results and apply the phenomenon.
	Thanks for watching!
</div>

Measures of verbal working memory, including list learning, are used in a variety of contexts as a quickly and easily obtainable measure of an individual&#8217;s cognitive ability. This is because memory span is known to correlate very reliably with IQ. In fact, memory span is a sub-test on many IQ tests. In clinical settings, verbal span can thus be used to determine whether illness or brain damage has had an effect on cognitive functioning in general, and as indicator of degenerative diseases such as Alzheimer&#8217;s.

measuring verbal working memory span

Source: Laboratory of Jonathan Flombaum&#8212;Johns Hopkins University

Why is it relatively hard to remember everything on a shopping list if it includes more than just a handful of items? Why is it possible to remember a phone number that one just heard, but not two or three phone numbers at once? Why is it difficult to remember names when several new people are introduced at the same time?
The answer has to do with the fact that over short-durations people rely on a specialized memory system called working memory. Unlike long-term memory, working memory has a very limited capacity. It is there so that information can be kept in mind, studied, manipulated, and then transferred to other memory and cognitive systems. But in order to serve in this active role, it needs to be selective, admitting only limited amounts of information at a time.
Experimental psychologists tend to think that people possess independent working memory systems for different kinds of information, with a major division between verbal and visual information. Each of these systems has an independent capacity limit.
To measure a person&#8217;s verbal working memory capacity limit&#8212;often called, his or her memory span&#8212;experimental psychologists often use a verbal list paradigm.
This video will demonstrate the measurement of verbal working memory span using a verbal list paradigm.

In terms of verbal memory span, one way to classify a person’s ability is as the longest list for which he/she performs better than 75% correct for all word positions. For this participant, that seems to be a list with five words (Figure 1), which makes the verbal working memory span five.
<img alt="List recall performance graph; accuracy vs. word position; multiple list lengths; data analysis." src="/files/ftp_upload/10006/10006fig1.jpg" ...

Source: Laboratory of Jonathan Flombaum&#8212;Johns Hopkins University

Why is it relatively hard to remember everything on a shopping list if it includes ...

To actively remember information over a short duration, Individuals rely on a specialized memory system called working memory.Unlike long-term memory, working memory has a very limited capacity, which allows selective information to remain active-to be studied, manipulated, and then transferred to other memory and cognitive systems.Researchers can measure the capacity limit of verbal working memory-the memory span-through the use of a verbal list paradigm. This paradigm involves the researcher reading word lists of varied lengths to subjects and then asking the subjects to repeat back the words in sequential order.This video demonstrates standard procedures for studying verbal working memory span by explaining how to design and conduct the experiment, as well as how to analyze and interpret the results.In this experiment, participants listen as an experimenter reads word lists with varying lengths. In this case, word positions among the varied-length lists are the independent variables. Participants are then asked to hold words in working memory while a list is read, after which they are asked to recall the words on the list in the same order. Recall accuracy, or how many words on

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verbal working memory with word lists

Verbal working memory is the short-term system people use to hold words and numbers in mind. It helps with tasks like remembering a shopping list, a phone number, or several new names. Unlike long-term memory, it has a very limited capacity.

Working memory lets information stay active for a short time so it can be studied, changed, and passed to other memory and thinking systems. Because it must stay selective, it only accepts limited amounts of information at once. Experimental psychologists often describe separate working memory systems for verbal and visual information, and each system has its own capacity limit.

To measure verbal working memory capacity, researchers use a verbal list paradigm. The result is often called memory span. This video demonstrates how verbal working memory span is measured with that list-based method.

Verbal Working Memory with Word Lists

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How People Learn Visual Patterns

Visual statistical learning is the way people pick up patterns in the visual world. Objects often appear near other objects in space and time, and learning those regularities can help with visual processing, including object recognition. People may learn these patterns automatically, quickly, and without conscious awareness. In the laboratory, this type of implicit learning is studied with an incidental-encoding paradigm. Participants watch a stream of nonsense objects while doing a cover...

motor learning in mirror drawing

Mirror Drawing and Procedural Learning

Mirror drawing is a standard lab task for studying procedural learning. It helps researchers observe how people acquire a new motor skill over time. The task is also useful for looking at the kind of learning that becomes smoother with practice, like driving a car. Learning and memory include many kinds of behavior and mental systems. Experimental psychologists often separate them into declarative memory and non-declarative memory. Declarative memory covers facts people can say out loud, such...

cognitive psychology

This collection describes a number of influential paradigms used to study complex mental processes underlying attention, perception, learning and memory.

Learn how psychologists measure verbal working memory span using a verbal list paradigm, and why short-term memory has limited capacity for words and numbers.

Verbal Working Memory with Word Lists | JoVE K12

Jonathan Flombaum

Overview

Experimental Design

Running the Experiment

Representative Results

Applications

Summary

Characteristics of Life

Biology is a natural science that studies life and living organisms, including their structure, function, development, interactions, evolution, ...

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Cell Structure

Background
Cells represent the most basic biological units of all organisms, whether it be simple, single-celled organisms like bacteria, or large, ...

Visualizing Onion and Cheek Cells
ExpandImmediately before the experiment, wash and peel onion bulbs for the class.
Remove the entire brown outer skin and ...

Visualizing Onion and Human Cells
ExpandIn this experiment you will prepare different types of cells from a plant and animal, onion and human ...

What are Cells?

Cell Diversity

The concept of a cell started with microscopic observations of dead cork tissue by Robert Hooke in 1665. Hooke coined the term &#34;cell&#34; based on the ...

Cytoplasm

The cytoplasm consists of organelles and a framework of protein scaffolds called the cytoskeleton suspended in an aqueous solution, the cytosol. The ...

The Nucleus

The nucleus is a membrane-bound organelle that acts as a control center in a eukaryotic cell. It contains chromosomal DNA, which controls gene expression ...

The Central Dogma

The DNA Helix

Nucleic Acids

DNA as a Genetic Template

Structure of a Gene

A gene is the fundamental unit of heredity. Every individual has two copies of each gene, one inherited from each parent. Although most people contain the ...

Chromosome Structure

Base-pairing and DNA Repair

What is Gene Expression?

A gene is a stretch of DNA that serves as the blueprint for functional RNAs and proteins. Since DNA is comprised&#160; of nucleotides and proteins are ...

RNA Structure

The basic structure of RNA consists of a string of ribonucleotides attached by phosphodiester bonds. Although most RNA is single-stranded, it can form ...

Types of RNA

Three main types of RNA are involved in protein synthesis: messenger RNA (mRNA), transfer RNA (tRNA), and ribosomal RNA (rRNA). These RNAs perform diverse ...

Transcription

Transcription is the synthesis of RNA from a DNA sequence by RNA polymerase. It is the first step in producing a protein from a gene sequence. ...

Translation

Translation is the process of synthesizing proteins from the genetic information carried by messenger RNA (mRNA). Following transcription, it constitutes ...

Ribosomes

Ribosomes translate genetic information encoded by messenger RNA (mRNA) into proteins. Both prokaryotic and eukaryotic cells have ribosomes. Cells that ...

Protein and Protein Structures

Proteins: From Genes to Degradation

From DNA to Protein

The flow of genetic information in cells from DNA to mRNA to protein is described by the central dogma, which states that genes specify the sequence of ...

Protein Folding

Proteins are chains of amino acids linked together by peptide bonds. Upon synthesis, a protein folds into a three-dimensional conformation, critical to ...

An Overview of Gene Expression

Gene expression is the complex process where a cell uses its genetic information to make functional products. This process is regulated at multiple ...

an-introduction-to-caenorhabditis-elegans

An Introduction to Caenorhabditis elegans

Caenorhabditis elegans is a microscopic, soil-dwelling roundworm that has been powerfully used as a model organism since the early 1970&rsquo;s.  It was ...

An Overview of Genetic Analysis

An organism&#8217;s physical traits, or phenotype, are a product of its genotype, which is the combination of alleles (gene variants) inherited from its ...

An Introduction to Cell Death

Necrosis, apoptosis, and autophagic cell death are all manners in which cells can die, and these mechanisms can be induced by different stimuli, such as ...

An Overview of Genetic Engineering

Genetic engineering &#8211; the process of purposefully altering an organism&#8217;s DNA &#8211; has been used to create powerful research tools and model ...

An Introduction to Cell Division

Cell division is the process by which a parent cell divides and gives rise to two or more daughter cells. It is a means of reproduction for single-cell ...

An Overview of Genetics and Disease

Many human diseases are associated with mutations or variations in genetic sequences. Some of these genetic variants are heritable, passed down from ...

an-introduction-to-cellular-and-molecular-neuroscience

An Introduction to Cellular and Molecular Neuroscience

Cellular and molecular neuroscience is one of the newest and fastest growing subdisciplines in neuroscience. By investigating the influences of genes, ...

Annexin V and Propidium Iodide Labeling

Staining with annexin V and propidium iodide (PI) provides researchers with a way to identify different types of cell death&#8212;either necrosis or ...

an-introduction-to-developmental-genetics

An Introduction to Developmental Genetics

Development is the complex process through which a single-celled embryo transforms into a multicellular organism. Developmental processes are guided by ...

Bacterial Transformation: Electroporation

The term &#x201C;transformation&#x201D; refers cellular ingestion of foreign DNA.  In nature, transformation can occur in certain types of bacteria.  In ...

an-introduction-to-molecular-developmental-biology

An Introduction to Molecular Developmental Biology

Molecular signals play a major role in the complex processes occurring during embryonic development. These signals regulate activities such as cell ...

bacterial-transformation-the-heat-shock-method

Bacterial Transformation: The Heat Shock Method

Transformation is the process that occurs when a cell ingests foreign DNA from its surroundings. Transformation can occur in nature in certain types of ...

an-introduction-to-saccharomyces-cerevisiae

An Introduction to Saccharomyces cerevisiae

Saccharomyces cerevisiae (commonly known as baker&rsquo;s yeast) is a single-celled eukaryote that is frequently used in scientific research.  S. ...

Cell Cycle Analysis

Cell cycle refers to the set of events through which a cell grows, replicates its genome, and ultimately divides into two daughter cells through the ...

An Introduction to Transfection

Transfection is the process of inserting genetic material, such as DNA and double stranded RNA, into mammalian cells. The insertion of DNA into a cell ...

Chromatin Immunoprecipitation

Histones are proteins that help organize DNA in eukaryotic nuclei by serving as &#8220;scaffolds&#8221; around which DNA can be wrapped, forming a complex ...

An Overview of Epigenetics

Since the early days of genetics research, scientists have noted certain heritable phenotypic differences that are not due to differences in the ...

community-dna-extraction-from-bacterial-colonies

Community DNA Extraction from Bacterial Colonies

Source: Laboratories of Dr. Ian Pepper and Dr. Charles Gerba - The University of Arizona
Demonstrating Author: Luisa Ikner
Traditional methods of analysis ...

Cytogenetics

Cytogenetics is the field of study devoted to chromosomes, and involves the direct observation of a cell&#8217;s chromosomal number and structure, ...

embryonic-stem-cell-culture-and-differentiation

Embryonic Stem Cell Culture and Differentiation

Culturing embryonic stem (ES) cells requires conditions that maintain these cells in an undifferentiated state to preserve their capacity for self-renewal ...

DNA Gel Electrophoresis

DNA gel electrophoresis is a technique used for the detection and separation of DNA molecules. An electric field is applied to a gel matrix comprised of ...

Enzyme Assays and Kinetics

Enzyme kinetics describes the catalytic effects of enzymes, which are biomolecules that facilitate chemical reactions necessary for living organisms. ...

DNA Ligation Reactions

In molecular biology, ligation refers to the joining of two DNA fragments through the formation of a phosphodiester bond.  An enzyme known as a ligase ...

explant-culture-for-developmental-studies

Explant Culture for Developmental Studies

Explant culture is a technique in which living cells or tissues are removed from an embryo for continued development outside of the organism. This ex vivo ...

DNA Methylation Analysis

Methylation at CpG dinucleotides is a chemical modification of DNA hypothesized to play important roles in regulating gene expression. In particular, the ...

Expression Profiling with Microarrays

Microarrays are important tools for profiling gene expression, and are based on complementary binding between probes that are attached to glass chips and ...

Density Gradient Ultracentrifugation

Density gradient ultracentrifugation is a common technique used to isolate and purify biomolecules and cell structures. This technique exploits the fact ...

F&#246;rster Resonance Energy Transfer (FRET)

F&#246;rster resonance energy transfer (FRET) is a phenomenon used to investigate close-range biochemical interactions. In FRET, a donor photoluminescent ...

detecting-environmental-microorganisms-with-polymerase-chain-reaction

Detecting Environmental Microorganisms with the Polymerase Chain Reaction and Gel Electrophoresis

Source: Laboratories of Dr. Ian Pepper and Dr. Charles Gerba - Arizona University
Demonstrating Author: Bradley Schmitz
Polymerase chain reaction (PCR) is ...

Gel Purification

Gel purification is used to recover DNA fragments after electrophoretic separation. DNA recovery from an agarose gel includes three basic steps: binding, ...

Detecting Reactive Oxygen Species

Reactive oxygen species are chemically active, oxygen-derived molecules capable of oxidizing other molecules. Because of their reactive nature, there are ...

Gene Silencing with Morpholinos

Morpholino-mediated gene silencing is a common technique used to study roles of specific genes during development. Morpholinos inhibit gene expression by ...

development-and-reproduction-of-the-laboratory-mouse

Development and Reproduction of the Laboratory Mouse

Successful breeding of the laboratory mouse (Mus musculus) is critical to the establishment and maintenance of a productive animal colony. Additionally, ...

Genetic Crosses

To dissect genetic processes or create organisms with novel suites of traits, scientists can perform genetic crosses, or the purposeful mating of two ...

drosophila-melanogaster-embryo-and-larva-harvesting-and-preparation

Drosophila melanogaster Embryo and Larva Harvesting and Preparation

Drosophila melanogaster embryos and larvae are easy to manipulate and develop rapidly by mechanisms that are analogous to other organisms, including ...

Construct an explanation based on evidence for how the structure of DNA determines the structure of proteins which carry out the essential functions of life through systems of specialized cells.

HS-LS1-1.

Verbal Working Memory with Word Lists

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