BIO.3 REVIEW

Meiosis

Study this picture. Notice how a cell with four chromosomes turns into four different cells, each containing two chromosomes.

Meiosis results in half the original DNA

Each new sperm or egg cell has a different set of DNA, which is why you are different than your siblings.

Multiple Choice

How many chromosomes does a human somatic (body) cell have?

• 2

• 14

• 23

• 46

Multiple Choice

What process, and which types of cells are represented by the diagram?

• Mitosis, somatic cells

• Mitosis, gametes

• Meiosis, somatic cells

• Meiosis, gametes

​Karyotypes

​Karyotype: a picture of chromosomes.

​- Can be used to diagnose chromosomal disorders

​- You can also see the gender

​

​Autosomes: pairs 1-22 (chromosomes 1-44) that do NOT code for sex

​

​Sex chromosomes: the last pair (pair 23) that do code for sex

​XX: female sex chromosomes

​XY: male sex chromosomes

​This is a male because it has one X and one Y

​Down syndrome

​Caused by Trisomy 21

​--> 3 chromosomes in pair 21

​--> Symptoms: speech delays, intellectual disabilities

​Klinefelter

​XXY ... a male who inherited an extra X chromosome

​Turner's syndrome

​A female who is missing an X chromosome

Multiple Choice

Determine the sex of the individual whose karyotype is displayed in the image.

• female

• male

Multiple Choice

Determine the sex of the individual whose karyotype is displayed in the image.

• female

• male

Multiple Choice

Which of the following is a karyotype for Turner Syndrome?

Multiple Select

SELECT ALL THAT APPLY: Sex Chromosomes:

• Pair #23

• Determine whether you're male / female

• Pairs #1-22

• Every chromosome except sex chromosomes

Multiple Select

SELECT ALL THAT APPLY:

• Male

• Female

• No chromosomal abnormalities

• Trisomy 21

Multiple Select

SELECT ALL THAT APPLY: Autosomes Chromosomes:

• Pair #23

• Determine whether you're male / female

• Pairs #1-22

• Every chromosome except sex chromosomes

Multiple Choice

Original DNA: CAT GAT CCA

New DNA: CAT TGA TCC A

What mutation occurred?

• deletion

• substitution

• tranverse

• insertion

Multiple Choice

DNA molecule segment is : TTACGCAAG

The mutated DNA segment is TTCGCAAG. This is an example of ___ mutation.

• Substitution

• Deletion

• Insertion

• Inversion

Multiple Choice

DNA molecule segment is : TTACGCAAG

The mutated DNA segment is TTACGCAAC. This is an example of ___ mutation.

• Substitution

• Insertion

• Inversion

• Translocation

Multiple Choice

What amino acid is represented by the codon CCA?

• Phenylalanine

• Tyrosine

• Leucine

• Stop codon

Multiple Choice

What would be the complementary RNA sequence for the following DNA sequence?

ATTCGT

• UAAGCA

• TAAGCA

• GCCTAC

• UGCUAC

Multiple Choice

What is the name of the process in which DNA is transcribed into RNA?

• Photosynthesis

• Protein Synthesis

• Translation

• Transcription

DNA, Chromosomes, & Genes

​

Multiple Choice

DNA stands for

• deoxyribonucleic acid

• ribonucleic acid

• deoxygenated nuclear acid

Multiple Select

Which are the correct DNA pairings? (choose 2

• Cytosine-Guanine

• Adenine-Cytosine

• Adenine-Thymine

• Thymine-Guanine

Punnett Squares

Dominant vs. Recessive

• —Dominant - Masks the other trait; the trait that shows if present

  —Represented by a capital letter

• Recessive – An organism with a recessive allele for a particular trait will only exhibit that trait when the dominant allele is not present; 

• Recessive – lower case

Practice

• 
  

• —TT - Represent offspring with straight hair

  —Tt - Represent offspring with straight hair

  —tt - Represents offspring with curly hair

• 
  

Multiple Choice

Which of the following genotypes is homozygous dominant?

• aa

• Aa

• AA

Multiple Choice

Which of the following alleles is purebred recessive?

• Tt

• tt

• TT

Genotype vs. Phenotype

• —Genotype – The genetic makeup of an organism; The gene (or allele) combination an organism has.

  —Example: Tt, ss, GG, Ww

• —Phenotype – The physical characteristics of an organism; The way an

  organism looks

Homozygous vs. Heterozygous

• Homozygous – Term used to refer to an organism that has two identical 

• Heterozygous - Term used to refer to an organism that has two different 

Multiple Choice

What type of Genotype is this: DD?

• Homozygous

• Heterozygous

Multiple Choice

What type of Genotype is this: Aa?

• Homozygous

• Heterozygous

Multiple Choice

What type of Genotype is this: AA?

• Homozygous

• Heterozygous

Punnett Squares

• —Punnett Square – Diagram showing the gene combinations that might result from a genetic cross

• 
  

Multiple Choice

How chance the offspring born from this cross will have a homozygous dominant genotype?

• 25%

• 50%

• 75%

• 100%

Multiple Choice

Fill in the Yellow Box

• AA

• Aa

• aa

Multiple Choice

This type of inheritance pattern is a MIXTURE of two traits. This is known as ---

• incomplete dominance.

• codominance

Multiple Choice

When one allele is not dominant over the other, resulting in both traits expressed in a heterozygous individual.....

• Incomplete Dominance

• Codominance

Multiple Choice

Which of the following genotypes code for the blood type AB?

• I^A I^A and I^A I^B

• I^A I^B only

• I^A I^B and I^B i

• ii only

Pedigrees

Multiple Choice

How are women represented on a Pedigree?

• Triangle

• Circle

• Square

• Octagon

Multiple Choice

How are men represented on a Pedigree?

• Rectangle

• Circle

• Square

• Hexagon

Multiple Choice

If a circle or square is completely shaded in, that means ________________.

• he or she is dominant.

• he or she is missing a trait.

• he or she is affected.

• he or she is a carrier.

Multiple Choice

If mostly males are affected in the pedigree, the disorder is said to be ________________.

• Dominant

• Recessive

• Autosomal

• Sex-linked

Multiple Choice

If both males and females are affected int the pedigree, the disorder is said to be ________________.

• Autosomal

• Sex-linked

• Dominant

• Recessive

Multiple Choice

A _____________ is a diagram that shows the genotypes and phenotypes of organisms from one generation to the next

• Dihybrid cross

• Punnett square

• Pedigree

• Monohybrid cross

Explanation Slide...

Turner is monosomy of the X chromosome,