2nd Semester Final Study Guide

1.     Differentiate between

a.     Homozygous/Heterozygous

                                               i.     Same alleles/Different alleles

b.     Dominant/Recessive

                                               i.     Capital letters/Lowercase letters

                                              ii.     Dominant masks recessive

c.      RNA/DNA

                                               i.     DNA – double helix, contains thymine, deoxyribose nucleic acid, stores genetic information

                                              ii.     RNA – single stranded, contains uracil, ribose sugar, codes for amino acids

d.     Genes/Alleles

                                               i.     Gene – a physical trait (eye color)/Alleles – all the possible combinations of a gene (blue, green, hazel)

e.     Haploid/Diploid

                                               i.     Haploid – half the number of chromosomes (sex cells)

                                              ii.     Diploid – 2 sets of chromosomes one from each parent (body cells)

f.      Transcription/Translation

                                               i.     Transcription – copying the DNA strand onto mRNA/Translation – creating a proteins using the mRNA strand

g.     Positive Feedback/Negative Feedback

                                               i.     Positive feedback – going farther away from normal before returning to normal/Negative feedback – responding to a change and going back to normal

Evolution

2.     Name 3 adaptations for a polar bear that would make it well suited for its environment.

a.     Thick white fur, ability to swim, sensitive nose, padded feet, binocular vision.

3.     Complete the sentence. Evolution is genetic change in a population over time.

4.     Explain why variation is essential in order for natural selection to occur.

a.     There must be a variety of traits in a habitat in order for nature to “select” the traits that give an organism the biggest advantage to survive and reproduce/pass on their beneficial genes.

5.     Explain why this sentence is false: “Sam the tortoise and friends stretched their necks to adapt to their changing environment and access more food.” Change this sentence to make it true.

a.     Lamarck’s theory is false because only genetic information is passed down, not use or disuse.

b.     Sam the tortoise and friends were born with slightly longer necks than the other which gave them access more food. This allowed them to survive longer and reproduce more than the other tortoises.

Genetics

6.     How many chromosomes do humans have?

a.     46

7.     How many of those chromosomes are sex chromosomes?

a.     2

8.     If B= black fur, b= brown fur and Black is dominant over brown, what proportion of the offspring will be homozygous Black fur if the parents are Bb x Bb?

a.     25%

9.     The Tanner Family has 3 girls. What is the probability of the next child being another girl?

a.     50% (cross XX x Xy)

10.   What is a sex-linked trait?

a.     A trait that is found on one of the sex chromosomes.

11.   Name a disease that is sex linked.

a.     Colorblindedness

12.   Carrie is a girl whose mom has normal vision and is not a carrier for the colorblind gene. Carrie’s dad is colorblind. What are the chances that Carrie is colorblind? What are the chances that her brother will be colorblind?

a.     0% chance Carrie or her brother will be colorblind

13.   If R is red and r is white in flowers, what is the color of each flower given the following situation

a.     Rr (R is dominant to r)

                                               i.     Red

b.     Rr (codominance)

                                               i.     Red with white spots

c.      Rr (incomplete dominance)

                                               i.     Pink

14.   Make a pedigree for Joe. Joe has 3 sisters. Joe’s mom has 3 brothers. Joe’s dad has 1 brother and 1 sister. Both of Joe’s parents have a set of parents.

DNA

15.   Why is DNA replication called ‘semi-conservative replication’?

a.     Only half of the DNA strand is copied or “conserved”.

16.   What are the four bases found in DNA? RNA?

a.     ATGC/AUGC

17.   How do the four bases pair up?

a.     A-T(U), G-C

18.   Which RNA strand copies DNA? mRNA or tRNA?

a.     mRNA

19.   Which RNA strand retrieves the appropriate amino acid for protein synthesis? mRNA or tRNA?

a.     tRNA

20.   What is the complementary DNA strand to:

a.     CGC TAT TTA GCA ATG

b.     GCG ATA AAT CGT TAC

c.      ATG CAT GGA ATT TCC

d.     TAC GTA CCT TAA AGG

21.   What is the complementary RNA strand to:

a.     ACC GAT TTA CCA GCA

b.     UGG CUA AAU GGU CGU

c.      TTT ACT AGG TCA CAG

d.     AAA UGA UCC AGU GUC

22.   What is a codon?

a.     3 base pairs that code for a protein (ex. AUA, GCA)

23.   How many bases are in 5 codons?

a.     15 (3x5)

24.   Put the following events in order:

a.     Proteins are made

b.     mRNA leaves nucleus

c.      mRNA copies one side of the DNA

d.     tRNA brings the correct amino acid to mRNA to form amino acid chain

e.     C, B, D, A

Human Systems

25.   What is the function of the myelin sheath?

a.     Speeds up neural communication (100x faster)

26.   What are the parts of a neuron? Draw a neuron and label all the parts.

a.     Dendrites, cell body, axon, myelin sheath, axon terminals.

27.   What is the CNS? What is it made of?

a.     Central Nervous System – brain and spinal cord

28.   What is the PNS? What is it made of?

a.     Peripheral Nervous System – all other nerves in the body

29.   What are the systems of the human body?

a.     Circulatory, Nervous, Immune, Integumentary, Digestive, Respiratory, Skeletal, Muscular, Endocrine, Excretory.

30.   Choose 2 systems from above and state their structure and function.

a.      

31.   What is the non-specific defense made of?

a.     Skin, tears, sweat, mucus, hair.

32.   What are T-Cells? Name the 3 types.

a.     Helper T-Cells (identify the pathogen)

b.     Killer (activated) T-Cells – seek and destroy infected body cells

c.      Memory T-Cells – store information to quickly identify the pathogen at a later time.

Health

33.   What is a calorie?

a.     A unit of energy/the energy required to raise 1mL of water by 1 degree Centigrade

34.   What is healthy eating? Why is it important?

a.     Healthy eating – eating a balanced diet consisting of all the major food groups (grains, vegetables, fruits, meats, dairy) and low in sugar. Watching calories/serving sizes to avoid overeating.

b.     Importance – keeps body at a healthy weight, minimizes health risks such as diabetes, keeps the heart running strong, and reduces risk of chronic illness.

35.   What is an STI/STD?

a.     Sexually Transmitted Infections (curable)/Sexually Transmitted Diseases (symptoms can be treated) are pathogens that are acquired by unprotected sexual contact (ex. Herpes, HIV, Chlamydia).

36.   How can we protect ourselves from sexually transmitted disease/infections?

a.     100% effective method – abstinence.

b.     Next best method – condoms (female and male)

c.      Use protective methods to reduce risk of acquiring an STI/STD.