Biology Exam Review Test 2

In which direction does DNA replication take place?

5' to 3'

Non- disjunct chromosomes lead to diseases like

Downs Syndrome

Describe the sequence of mitotic cell cycle for a pair of chromosome

G2, Mitosis, G1, S

Cell organelles

Mitochondria

Mitochondria are observed in plant cells that contain chloroplasts. Why do you find mitochondria in photosynthetic tissue?

Mitochondria are required to break down sugars and other materials for energy

Crossover

meiosis

Isotonic

no osmosis

Plasma Membrane

osmosis

Which type of point mutation would have no effect on gene expression?

silent

The M check point

spindle checkpoint

1) RNA is single stranded, has uracil in place of thymine, contains ribose sugar and not deoxyribose sugar 2) RNA is at least of 3 types: mRNA, tRNA, and rRNA 3) mRNA is transcribed using RNA polymerase 4) tRNA and rRNA and not transcribed

1,2,3 is true

If the sequence of the 5'-3' strand is AATGCTAC, then the complementary sequence has the following sequence:

3' -TTACGATG-5'

A poly-A sequence is added at the:

3'- end of a transcript in the nucleus

How many nucleotides are in 12 mRNA codons?

36

How many chromosomes are in G2 phase of human muscle cell

46 pairs but connected at centromere

What are some differences between DNA and RNA?

DNA contains deoxyribose and thymine, while RNA contains ribose and uracil.

Replication

DNA to DNA

transcription

DNA to mRNA

Central Dogma

DNA to mRNA to Proteins

What is the flow of information for the synthesis of proteins according to the central dogma?

DNA to mRNA to protein

The AUC and AUA codons in mRNA both specify isoleucine. What feature of the genetic code explains this?

Degeneracy

There are multiple nuclei in the eukaryotic cell each separated by its own membrane

False

If a doctor injected a patient with what was labeled as an isotonic saline solution, but then the patient died, and an autopsy revealed that several of the patient's red blood cells had burst, would it be true that the injected solution was really isotonic? Why or why not?

False, the solution was hypotonic

At which of the cell cycle checkpoints do external forces have the greatest influence?

G1

There are called the garbage disposal units or suicide bags of cells

Lysozomes

What part of meiosis is most similar to mitosis

Meiosis II

Exocytosis is of 2 types Phagocytosis and Pinocytosis, while Endocytosis is only of one type.

No

Crossover occurs in

Prophase 1

Which is the longest phase in cell cycle?

S

Meselson and Stahl's experiments proved that DNA replicates by which mode?

Semi-conservative

Active transport across the membrane means the process needs ATP for transporting molecules across the membrane.

True

Choline, ethanol amine, serine and inositol are four organic molecules that are attached to phosphate group in the phospholipids and only serine is negatively charged, others are neutral

True

Lipid bilayer means an arrangement where to layers of lipid molecules are arranged in such a way that polar heads make the outer boundary and hydrophobic tails are arranged on inner side.

True

Passive transport across the membrane could be grouped into two categories, diffusion and facilitated diffusion. Both occur without requirement of ATP.

True

Rough endoplasmic reticulum is called so because it has ribosome attached to it.

True

The fluid mosaic model of the plasma membrane describes the plasma membrane as a combination of phospholipids, cholesterol, and proteins which can move with respect to each other

True

Uncontrolled Mitosis leads to human diseases like

Tumors and Malignant tumors

A diploid cell has how many times the number of chromosomes as a haploid cell?

Twice

Water moves via osmosis across plasma cell membranes in which direction?

from an area of with a high concentration of water to one of lower concentration

What portion of a DNA contains Okazaki fragments?

lagging strand

G2 check point checks for

mainly DNA duplication

Which organelles would be present in high numbers in the leg muscles of a marathon runner?

mitochondria

What are the building blocks of nucleic acids?

nucleotides

Cytokinesis differs between plants and animals

plant cells develop a cell plate

What process transfers heritable material to the next generation?

replication

The sequence that signals the end of transcription is called the:

stop codon

What are introns?

untranslated DNA sequences in a gene

Over the last two decades RNA has been found to be of further types: miRNA (micro RNA) and siRNA (small interfering RNA. miRNA are usually 20 nucleotide long and have biological functions. siRNA are again small RNA moleucles but they interfere with metabolic processes. Do you think in coming years these RNA will prove to be biologically more involved than we know now.

yes