DL Week 3

Monday Week 1 P5 L4

Review 1.1, 1.2 DNA

PRACTICAL 1.2A: DNA extraction from banana

Gently "mush" the banana in the Ziplock bag for about a minute until all the lumps are gone and the banana almost looks like custard.
Fill a cup with the hot water and 1 teaspoon of salt and stir to dissolve.
Pour the saltwater mix into the bag. Close the bag and very gently squeeze and move the saltwater and banana mush together for 30 - 45 seconds.
Add the dishwashing soap into the bag and gently mix the contents. Try to avoid making too much foam.
Place the coffee filter in a clear glass cup, securing the top of the filter around the lip of the cup.
Pour the mix into the filter and let it sit until all of the liquid drips down into the cup.
Remove and discard the used coffee filter.
Tilt the glass and slowly add cold alcohol down the side of the cup. You want the alcohol to form a layer on top of the banana mix, staying separated, so be careful not to pour it too fast. Make a layer of alcohol that is about 2-3cm thick.
After the alcohol layer is set up, wait for eight minutes. You may see some bubbles and cloudy material moving around in the alcohol. This is the DNA pieces clumping together.
Use the wooden stirrer to start poking the DNA in the alcohol layer. Spin the stirrer it in place to start gathering the DNA. Take a closer look at the DNA.

10 WDWCF 1.2a DNA Extraction Prac.docx

Wednesday Week 1 P3 L3

1.3 Relate DNA base sequences to the production of particular proteins, resulting in an organism’s traits.

1.4 Draw and interpret a flowchart describing the relationship between DNA, genes and chromosomes.

TASK 1.3A

Make summary notes for Parts 1-4 below:

View video [1.07 mins] and read What are Proteins https://learn.genetics.utah.edu/content/basics/proteins

2. Read and view DNA and genes [1.03 mins] https://learn.genetics.utah.edu/content/basics/dna

3. Scootle: Genes: Introduction to Genes https://www.scootle.edu.au/ec/viewing/L5917/L5917/index.html# (need code)

4. Stile Review Lesson: Decoding Life 1.1 DNA and Genes and complete Qs. Carefully read instructions, some Qs have more than one expected answer. https://stileapp.com/au/RC_NSW-551/subject-306846/lesson-2050615/worksheet-15416160 Two students to join [www.stileapp.com/join class code A7ACWW]

Thursday Week 1 P1&2 L4

ONGOING TASK

Glossary of terms:

DNA, gamete, gene, replication, traits

How can genes be expressed in an individual?

Check-in : how are you going?
Complete https://askabiologist.asu.edu/monster-maker-game/introduction.html

Review 1.1-1.4

Read 1.3 DNA Language of Life

2. View video Gene Expression [5.31 mins] https://www.youtube.com/watch?v=EHm9Nu4rt08

DNA song 2 [4.32 mins] https://www.youtube.com/watch?v=wdhL-T6tQco
DNA Song 3 [1.56 mins] https://www.youtube.com/watch?v=T5gEIViVAPw

Challenge

But how are genes passed on?

DNA Replication (overview)

All forms of reproduction require that DNA be replicated in forming the new individual.

Tx p 11: Replicating the DNA

Apart from red blood cells, all the cells in your body have nuclei that contain chromosomes made of DNA. Each cell contains exact copies of the chromosomes that were in the original zygote that became you. This means that it must be possible to copy DNA molecules. The process of copying DNA is known as Replication.
In the first step of replication, the strands of the double helix separate from each other (much the same way as a zip opens.)
The bases are then exposed.
Within the nucleus there are individual nucleotides that are not part of a DNA chain.
In step 2, these nucleotides pair up with the exposed bases following the rules of complementary base pairing. In step 3, the sugar and phosphate molecules bond with neighbouring nucleotides and new strands of DNA are formed. Replication occurs on both of the exposed strands of DNA, and the result is two identical molecules of DNA.

View videos

[3.27 mins] DNA Replication-3D https://www.youtube.com/watch?v=TNKWgcFPHqw
DNA replication https://www.youtube.com/watch?v=z685FFqmrpo&feature=related [1.02 mins]

Scootle activity: Genes-DNA Replication https://www.scootle.edu.au/ec/viewing/L5917/L5917/index.html#

Friday Week 1 P2 R22

1.5 Model the steps to identify the role of meiosis (cell division) in halving the number of chromosomes as gametes (male and female sex cells) are formed.

1.6 Describe how fertilisation combines the chromosomes in the male and female sex cells to form new combinations of genes in the zygote.

Cells are limited in the size they can reach, so when a multi-cell organism grows, its individual cells do not grow bigger, it makes new cells. When cells reproduce themselves, the DNA in the nucleus must replicate (make a copy of) itself.

The following short video is just to show in simple form how that quite complex process happens. It is not required learning (it is in the Y12 Biology course.)

View video: