Download Genetics - Tour of the Basics

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Date:
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Life Science
Tour of the Basics
Genetics
Mr. Yescavage
Learn.genetics.utah.edu/content/begin/tour
1.
Instructions providing all of the information necessary for a living organism to grow and live
reside in the ______________ of every cell. These instructions tell the cell what
_______________ it will play in your body.
2.
The instructions come in the form of a molecule called _______________. DNA encodes a
detailed set of plans, like a _______________, for building different parts of the cell.
DNA stands for __________________________ Acid.
3.
The DNA molecule comes in the form of a twisted ladder shape scientists call a
_______________. The ladder’s rungs are built with the four letter DNA alphabet: _____,
_____, _____, and _____. These alphabet pieces join together according to special rules. A
always pairs with _____, and C always pairs with _____.
4.
The DNA strand is made of letters, the letters make words, the words make sentences. These
“sentences” are called _______________. Genes tell the cell to make other molecules called
_______________. Proteins enable a cell to perform special functions, such as working with
other groups of cells to make hearing possible.
What is a Gene?
5.
Genes are _______________ manuals for our bodies. They are the directions for building all
the proteins that make our bodies function.
6.
Genes are made of _______________. One strand of our DNA contains many
_______________. All of these genes are needed to give instructions for how to make and
operate all parts of our bodies.
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7.
For example. Blood contains _______________ cells that transport _______________ around
our bodies. The cells use a protein called _______________ to capture and carry the oxygen.
Of our _______________ genes, only a few contain the instructions for making hemoglobin
proteins. The remaining genes contain the instructions for making other parts of our bodies.
8.
If our hemoglobin gene is normal, the hemoglobin protein works fine. But if the instructions in
that gene are changed, or _______________, changes in the hemoglobin protein could result.
One such mutation causes a disorder called _______________ anemia.
9.
Genes contain instructions for building proteins, which are involved in all sorts of things.
Hemoglobin protein is just one example. Other proteins such as the enzymes that produce
_______________
in
your
eyes
and
_______________,
responsible
for
growing
_______________ and nails, are also produced by genes.
What is a Chromosome?
10.
Each cell in our body contains a lot of DNA. In fact, if you pulled the DNA from a single
human cell and stretched it out, it would be ____________________ long! That’s about as long
as a _______________. How does all of that DNA fit into a cell? The DNA is packaged into
compact units called _______________.
11.
The packaging of DNA into a chromosome is done in several steps, starting with the
____________________ of DNA. Then the DNA is wrapped around some _______________.
12.
These proteins are packed tightly together until they form a _______________. Chromosomes
are efficient storage units for __________.
13.
How many chromosomes does one cell hold? The correct answer to this depends on whether
you’re a fish or a fly, or a human. Each human cell has __________ chromosomes. All the
DNA is organized into two sets of __________ chromosomes. We get genetic material from
both of our _______________ - that’s why children look like both their mom and dad.
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14.
Look at this set of chromosomes. You can see that matching chromosomes have been lined up
in pairs – one each from mom and dad. Although the DNA double helix is too small to see,
chromosomes can be viewed with a _______________, as in this picture. There are
__________ sex chromosomes that determine whether you are male or female. In the picture
the sex chromosomes are labeled __________ and __________. The set of chromosomes in
this picture are from a male – you can tell because females do not have a __________
chromosome. Instead, they have two __________ chromosomes.
15.
Not all living things have _______________ chromosomes, like humans. Mosquitos, for
instance have _____. Onions have _____. Carp have _____.
What is Protein?
16.
Proteins are the machines that make all living things _______________, from viruses to
daffodils, spiders to sea lions, and everything in between. How do proteins work in the body?
Our bodies are made up of about _______________ cells! Each of these cells is responsible for
a specific job. Every cell contains thousands of different proteins, which work together as tiny
machines to __________ the cell. You can think of proteins as parts of a car engine – each part
looks different, and they all do separate jobs to make the engine run.
17.
Nerve _______________ are responsible for the sensation of pain. They send the pain signal
from this person’s big toe to his _______________ almost instantly!
18.
Our nerve networks are made up of _______________ cells arranged end-to-end, like a
telephone line, to transmit the pain signal. The receiving end of each cell in the line contains
special proteins on its surface, called _______________ proteins. Receptor proteins are
responsible for picking up the _______________ and passing it along to the next cell.
19.
Did you notice that these nerve cells aren’t round? Instead, they’ve grown _______________,
which help them communicate with their neighbors in the line. Special proteins called
_______________ proteins help cells extend these branches and hold them in place. Structural
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proteins are like _______________, stacking together to form column-like supports that give
the cell its shape. These proteins are just two of thousands that help the nerve cell do its job.
Every cell in your body is just as _______________.
20.
In real life, proteins are a lot smaller that this. Even with the most powerful electron
microscope, you would have trouble seeing them! Scientists use _______________ programs
to model protein structure and function.
21.
Cells use the information encoded in their genes, which are a sort of protein _______________,
as the “blueprint” for making proteins. Each gene in the DNA _______________ information
about how to make an individual protein.
22.
When a cell needs to make a certain protein, specialized machinery within the cell’s nucleus
reads the gene and then uses that information to produce a molecular _______________ in the
form of RNA, a molecule very similar to DNA.
23.
RNA moves from the nucleus into the cytoplasm of the cell. Once there, the cell’s proteinmaking machinery, the _______________ reads the message and produces a protein that
exactly matches the specifications laid out in the gene.
24.
Once made, the _______________ travels to the part of the cell where it is needed and begins
to work. Each step in making a protein itself requires the work of highly _________________
proteins. Can you see why a cell needs _______________ of different proteins to function.
What is Heredity?
25.
Why do children look like their parents? Why do brothers and sisters resemble each other? This
is because we “inherit” _______________ from our parents. The passing of traits from parents
to child is the basis of _______________.
26.
Where exactly are our traits? Our _______________ encode the instructions that define our
_______________. Each of us has thousands of genes, which are made of _______________
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and reside in our chromosomes. The _______________ we grow up and live in also helps
define our traits. For example, while a person’s genes may specify a certain hair color,
_______________ to chemicals or sunlight can change that color.
27.
How do we get traits from our parents? Humans have __________complete sets of
__________ chromosomes (2x23 = 46 total). When parents conceive a child, they each
contribute one complete set to the child. In this way, parents pass __________ to the child.
28.
Every child receives _______________ of its chromosomes from the mother and half from the
father. This transfer takes place at conception, when the father’s _______________ cell joins
with the mother’s _______________ cell. While most cells in our bodies contain two sets of
chromosomes (2x23 = 46), sperm and eggs cells each have only __________ set (23). When
they join, they create a single cell, called a _______________ which has two sets of
chromosomes (46). The cell will _______________, ultimately developing into a child.
29.
Each parent contributes one complete set of __________________ to the child. This set can
contain chromosomes from both of the parent’s two sets. The only rule is that the child must
receive exactly ___________ of each chromosome.
30.
Since the parents contribute chromosomes _______________ to each new child, every child
inherits a ________________ set of chromosomes.
31.
As a result, every child will have a unique combination of _______________. Some will
resemble the _______________, and some will resemble the _______________. Still others
will be unique, a product of the _______________ combination of chromosomes.
32.
What will happen when one of these babies grows up and starts a family? She will contribute a
_______________ of her own chromosomes to each new child. This is how some
_______________ are passed through many ____________________.
What is a Trait?
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33.
What is a trait? A trait is a notable _______________ or _______________ in a person. Each
of us has a different combination of traits that makes us unique. Traits are passed from
generation to generation. We _______________ traits from our parents, and we pass them on to
our children.
34.
What types of traits exist? _______________ traits are characteristics of one’s physical
makeup. These include _______________, _______________, and _______________.
_______________ traits are characteristics of the way one acts. A sheepdog’s
_______________ instinct and a retriever’s desire to _______________ are good examples of
behavioral traits. ____________________ to a medical condition. An increased risk of getting
a certain type of disease is also a type of trait that can be passed from parent to child. Some
examples of such diseases include _______________ cell anemia, _______________ fibrosis,
_______________ disease, _______________, and certain types of _______________ illness.
35.
What defines our traits? The instructions encoded in our genes play a role in defining traits. But
the non-genetic or ____________________, influences in our lives are just as important in
shaping our traits. Sometimes these environmental factors can even _______________ a trait!
End of the Note Taking Section: Pay close
attention to the following material that is being presented!
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