Exam 4

Photo-synthesis

100

Most plants appear green because chlorophyll _____________ (absorbs or reflects) green light.

reflects! 

Chlorophyll does not absorb green wavelengths of light 

200

T or F: The Calvin cycle can happen during the night. 

True (light independent reaction)

300

What is the name of the sugar precursor molecule produced at the end of the Calvin cycle in photosynthesis?

G3P 

400

What supplies the electron that is lost in PSII of photosynthesis? 

Water 

(show diagram) 

500

Plants need carbon dioxide from their environment to produce glucose during which stage of photosynthesis?

The light independent stage (Calvin Cycle)

Cell Cycle + Cancer

100

The phase that is a non-dividing state occupied by cells that have left the cell cycle.

G0 phase  

200

T or F: Normal cells grow and divide continuously.

False

300

The cell cycle is regulated by what proteins?

Cyclin and Cyclin-dependent kinases

400

Which checkpoint involves ensuring all DNA has been replicated and “no” errors exist?  

G2 

500

Name the three tumor cell characteristics.

•No need for normal growth signals

•Loss of Anchorage dependence

•Loss of Density dependent inhibition

Mitosis/Meiosis

100

Gametes are considered to have half of the genetic info so it is called? 

Haploid

200

Cells spend the majority of their lives in what phase?

Interphase

300

The mitotic phase involving microtubules to separate sister chromatids to opposite poles of cell is called. 

Anaphase 

400

T or F: In Meiosis II, there are two cells that go through each of the phase at the same time. 

True 

500

In what stage of Meiosis does crossing over (exchange of genetic info) occur? 

MI - Prophase I 

Mendel + genetics

100

The alternative versions of a gene are called….

Alleles (ex: gene for eye color could either be blue, black, brown etc..) 

200

Why did Mendel choose pea plants? (one reason)

• Short generation time 
• Large numbers of offspring
• Can self-fertilize (true breeding/self-pollinate) or cross-pollinate (hybrids)

300

If an individual has a dominant phenotype but were don’t know if it's either: heterozygous dominant or recessive, what can we do?

A test cross can be done my breeding mystery individual with a homozygous recessive individual. If any of the offspring display the recessive phenotype the mystery parent be heterozygous

400

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

Codominance

500

What type of dominance or cross do we see in this cross? (explain). 

Incomplete dominance 

• One allele is not completely dominant over the other. There is a blending with the heterozygous offspring. E.g. RR=Red, RW=Pink, and WW=white

In incomplete dominance, the phenotype of F1 hybrids is somewhere between the phenotypes of the two parental varieties

Punnett Squares!!

100

Tall (TT) is dominant to short (tt)

If Tom Holland is homozygous recessive, and he and Zendaya (heterozygous dominant) have children, use a Punnett Square to predict the most likely phenotypic ratio and genotypic ratio of height for their possible children.

genotype ratio = 1:1 (Tt to tt) 

phenotype ratio = 50% tall and 50% short 

200

In pea plants, Purple flowers (P) are dominant over white (p) flowers. What would be the genotype and phenotype ratio of the offspring of the following cross: 

a heterozygous purple plant crossed with a homozygous purple plant 

In pea plants, Purple flowers (P) are dominant over white (p) flowers. What would be the genotype and phenotype ratio of the offspring of the following cross: 

a heterozygous purple plant crossed with a homozygous purple plant 

Genotype = 1:1 (PP to Pp) 

Phenotype = 100% purple 

300

Some flowers are controlled by codominace. Red flowers (RR), white flowers (WW) and Speckled flowers (RW). Cross a red flower with a white flower.

What is the ratio of white, red, or speckled flowers? 

4 speckled 

Co-dominance: Both alleles contribute to the phenotype. Offspring will have combination of two alleles.

400

In dogs a gene for fur has 2 alleles. 

Dominant allele (F) = grey hair 

Recessive allele (f) = black hair 

A female dog is heterozygous. The male dog is heterozygous. Use a Punnett Square to predict the phenotype and genotype ratio of their possible puppies. 

Phenotype = 3:1 (grey to black) 

Genotype = 1:2:1 (FF to Ff to ff) 

500

A dihybrid cross, a cross between F1 dihybrids, can determine whether two characters are transmitted to offspring together as a unit or independently. When Mendel tested this what ratio did he observe? 

9:3:3:1