Friday Feb 10th DQQ

Feb 10th DQQ

This time around I give you some of the slides that we used as notes for you to "review" - Then you will answer questions along the way.

You GOT this :)

How genes/dna & chromosomes are

related

• Genes are ‘short’ Sections of dna that code for

specific proteins. These are found on
chromosomes (46 in humans) found in the
nucleus.

• Humans have approx.
20 - 25,000 genes that code
For > 100,000 different
proteins

Fill in the Blanks

Multiple Choice

Which statement best describes the relationship between cells, DNA, and proteins?

• DNA is composed of proteins that carry coded information for how cells function.

• Cells contain DNA that controls the production of proteins.

• Proteins are used to produce cells that link amino acids together into DNA.

•  Cells are linked together by proteins to make different kinds of DNA molecules.

Multiple Choice

Which word represents the basic unit of heredity in living organisms?

• gene

• zygote

• nucleus

• chromosome

HOMOLOGOUS CHROMOSOMES

* Homologous chromosomes are
chromosomes that are SIMILAR in
size, in shape, and in kinds of
genes.

* They are NOT identical because
each chromosome in a
homologous pair comes from one
of the two parents.

* Homologous chromosomes can
carry different forms of genes
known as Alleles.

HOMOLOGOUS
CHROMOSOMES

Multiple Choice

Specific versions of a gene are known as.....

• Proteins

• Alleles

• Phenotype

• Chromosomes

Multiple Choice

How are homologous chromosomes related?

• They are Genetically Identical

• They are genetic sisters

• 1 came from your mom and one from your dad

• They are dating

Multiple Choice

Two alleles for pea plant height are designated T (tall) and t (dwarf). These alleles are found on:

• genes

• sex chromosomes

• ribosomes

• homologous chromosomes

Multiple Choice

The genetic material of two different individuals of the same species is analyzed. One individual has brown eyes. The other has blue eyes. Which characteristic for eye color would be the same for both individuals?

• the allele

• the DNA sequence

• the amount of pigment

• the location of the gene

Multiple Choice

Fertilization of an egg leads to a diploid genome as a zygote is formed. Which characteristic is true of a diploid genome?

• There are two alleles per gene.

• There are two genes per allele.

• There are two genes per chromosome.

• There are two chromosomes per allele.

Dominant vs

Recessive Alleles

⦿ DOMINANT (use capital letter)=

ALWAYS expressed if present.
(does NOT mean its more
common!!!)

⦿ recessive (use lowercase

letter)= ONLY expressed if no
DOMINANT allele is present.
(does NOT mean its Rare!!)

⦿ Genotype = the set of ALLELES

(GENES) an organism has for a
trait (the two letters)

⦿ Phenotype = the detectable

trait (PHYsical trait) – this is
determined by the genotype

Genotype vs
Phenotype

ALLELES

⦿ Different versions of a gene.

⦿ You have TWO alleles of

EVERY gene (one from mom,
one from dad)

⦿ Can be dominant or

recessive

⦿ Dominant = ALWAYS

expressed if present. (does
NOT mean its more
common!!!)

⦿ Recessive = ONLY expressed if

no DOMINANT allele is
present. (does NOT mean its
Rare!!)

⦿ They are Randomly

segregated – each gamete
has an equal chance of
receiving either one of the
two alleles an individual has

HOW ALLELES ARE
REPRESENTED

⦿ Dominant allele = Capital

Letter

⦿ Recessive allele = Lower case

letter

⦿ *** Generally ONE letter for

each trait***

⦿ Genotype = the set of ALLELES

(GENES) an organism has for a
trait (the two letters)

⦿ Phenotype = the detectible

trait (PHYsical trait) – this is
determined by the genotype

GENOTYPE VS
PHENOTYPE

Multiple Choice

Which of the following correctly describes PHENOTYPE?

• A. The combination of genes an organism has

• B. The physical traits an organism demonstrates

Multiple Choice

Which of the following correctly describes GENOTYPE?

• A. The combination of genes an organism has

• B. The physical traits an organism demonstrates

WHAT DOES THIS MEAN?

⦿ If you exhibit the recessive

PHENOTYPE – there is only ONE
possible genotype – Two
RECESSIVE alleles.

⦿ If you exhibit the Dominant

Phenotype – there are TWO
possible genotypes.
Dominant/Dominant
(homozygous dominant) OR
Dominant/Recessive
(heterozygous)

GENOTYPES CONT.

⦿ Homozygous

◼ You have two of the SAME

alleles

◼ Can be homozygous

DOMINANT (TT)

◼ Or Homozygous RECESSIVE

(tt)

⦿ Heterozygous

◼ You have two

DIFFERENT

alleles (Tt)

SO HOW DOES GENOTYPE
RELATE TO PHENOTYPE?

⦿ Remember – if a dominant

allele is present THAT is what
is expressed.

⦿ So in the case of the eye

color, a brown eyed person
could be Bb OR BB

⦿ Also remember – the ONLY

way you can exhibit a
recessive trait is if you are
Homozygous RECESSIVE (ONLY
have the recessive alleles) so
again – a blue eyed person
could ONLY be bb.

Multiple Choice

Brown eyes are dominant. Blue eyes are recessive. Any genotype with a Big B are represent a person with _____ eyes.

• Blue

• Brown

Multiple Choice

Brown eyes are dominant. Blue eyes are recessive. What is the phenotype for the genotype bb?

• Blue

• Brown

Multiple Choice

Which statement best describes the relationship between an allele and a gene?

• An allele is a variation of a gene that can be expressed as a phenotype.

• An allele is the part of a gene that attaches to messenger RNA molecules.

• An allele is a segment of a DNA molecule that controls replication of a gene.

• An allele is the primary protein made by a gene found in a developing embryo.

Multiple Choice

having two of the same genes for the trait (sometimes called purebred).

• homozygous

• hetrozygous

• protein

• chromosome

Multiple Choice

What is a phenotype?

• The expression of a trait; physical appearance.

• refers to the genetic makeup of an individual

• An organism that has the same genes for a trait (ex. TT or tt)

• the passing of traits from parent to offspring

Multiple Choice

What does heterozygous mean?

• An organism that has the same genes for a trait (TT or tt)

• An organism that has different genes for a trait (Tt)

• When neither gene is fully dominant; offspring is a mixture of both

• the different forms of a trait (hair color--> brown, blonde, red

Multiple Choice

How do you classify the following genotype : Bb

• Homozygous Dominant

• Homozygous Recessive

• Heterozygous

Multiple Choice

How do you classify the following genotype : HH

• Homozygous Dominant

• Homozygous Recessive

• Heterozygous

Multiple Choice

How do you classify the following genotype : jj

• Homozygous Dominant

• Homozygous Recessive

• Heterozygous

Multiple Choice

If Purple Flowers (P) are dominant over white flowers (p), what would the phenotype be for a Pp genotype?

• Purple flowers

• White flowers

• Not enough information

Multiple Choice

If Purple Flowers (P) are dominant over white flowers (p), what would the phenotype be for a pp genotype?

• Purple flowers

• White flowers

• Not enough information

Multiple Choice

If Purple Flowers (P) are dominant over white flowers (p), what would the phenotype be for a PP genotype?

• Purple flowers

• White flowers

• Not enough information

Multiple Choice

If Brown eyes (B) are dominant over blue eyes (b), what would the phenotype be for a bb genotype?

• Brown Eyes

• Blue Eyes

• Green Eyes

Multiple Choice

If Brown eyes (B) are dominant over blue eyes (b), what would the phenotype be for a Bb genotype?

• Brown Eyes

• Blue Eyes

• Green Eyes

Multiple Choice

If Brown eyes (B) are dominant over blue eyes (b), what would the phenotype be for a BB genotype?

• Brown Eyes

• Blue Eyes

• Green Eyes