Water
Which kind of bonds can form between water molecules?
Hydrogen bonds
Which structure is found in animal cells?
- Cell wall
- Chloroplast
- Pili
- Mitochondria
Mitochondria
What is osmosis?
The movement of water molecules through a semi-permeable membrane from an area of low solute concentration to an area of high solute concentration.
What results from an unspecialized cell experiencing gradients of signaling chemicals?
A. Cell differentiation
B. Meiosis
C. Saltatory conduction
D. DNA replication
A. Cell differentiation
Which process results in somatic cells?
Mitosis
Describe the difference between a covalent bond and a hydrogen bond.
Covalent bonds are when electrons are shared. Hydrogen bonds are weak attractions cause between a slightly positive hydrogen atom and an electronegative atom.
What is the difference between prokaryotic and eukaryotic cells?
Eukaryotic cells have a true nucleus that encloses their DNA, while prokaryotic cells lack a nucleus and have their DNA freely floating in the cell.
Where is DNA contained within a cell?
Nucleus
Why are adult stem cells are preferred over embryonic stem cells?
- health benefit
- ethical benefit
What is a result of crossing over in meiosis?
A. Gene linkage
B. Non-disjunction
C. Haploid cells
D. Variation in gametes
D. Variation in gametes
What causes cohesion between water molecules?
Hydrogen bonds between adjacent water molecules.
Mutations have a range of consequences for organisms.
Outline how mutation can lead to cancer.
Mutations cause cancer by changing DNA sequences in cells, which makes them grow and divide without stopping.
Are viruses considered living or non-living? Why?
Non-living; need a host cell
What best describes stem cells?
A. Cells found only in the early embryo.
B. Multipotent embryonic cells that can differentiate into all cell types.
C. Totipotent stem cells that are found in specific niches in adults.
D. Pluripotent stem cells that may differentiate into blood cells.
D. Pluripotent stem cells that may differentiate into blood cells.
Which process occurs in both mitosis and meiosis?
A. DNA replication
B. Splitting of chromosome centromeres
C. Exchange of genetic material between chromatids
D. Pairing of homologous chromosomes at the equator of the cell
B. Splitting of chromosome centromeres
Explain why water molecules are considered polar.
Water is considered a polar molecule because it has an unequal distribution of electrical charge, with a partial negative charge near its oxygen atom and a partial positive charge near its hydrogen atoms
A mutation in which type of cell could be inherited?
A. Beta cell in the pancreas
B. T-cell in the lymph
C. Sperm cell in the testis
D. Skeletal muscle cell in the diaphragm
C. Sperm cell in the testis
What is the role of DNA polymerase during DNA replication?
A. It adds nucleotides to the growing strand.
B. It adds nucleotides to the template strand.
C. It builds messenger RNA.
D. It carries out translation.
A. It adds nucleotides to the growing strand.
In mammals, mature red blood cells are specialized in that they lack nuclei, mitochondria or ribosomes. Which statement applies to red blood cells?
A. No chemical reactions take place within their cytoplasm.
B. They cannot produce new enzymes.
C. Materials cannot enter red blood cells.
D. Materials cannot exit red blood cells.
B. They cannot produce new enzymes.
What is produced by meiosis in a cell of a male animal?
A. Four gametes, each with the same number of chromosomes
B. Two gametes, each with the same number of chromosomes
C. Four gametes, each with different numbers of chromosomes
D. Two gametes, each with different numbers of chromosomes
A. Four gametes, each with the same number of chromosomes
What is the benefit to living organisms that water has a high specific heat capacity?
Aquatic environments do not have a great fluctuation in their temperature.
Mutations and sexual reproduction both play a role in generating variation, upon which natural selection acts. What describes how variation is generated?
I. Mutations generate new alleles.
II. Mutations generate new combinations of alleles.
III. Sexual reproduction generates new alleles.
A. I only
The antibiotic rifampicin is widely used to treat bacterial infections. It kills bacterial cells by interfering with transcription during protein synthesis. Which process would be directly prevented by rifampicin?
A. Base pairing between mRNA codons and tRNA anticodons
B. Bonding between amino acids
C. Movement of tRNA to the ribosome
D. Synthesis of mRNA from DNA
D. Synthesis of mRNA from DNA
Undifferentiated cells can become specialized to perform specific functions in a multicellular organism.
What accounts for the differences in these cells?
A. Their chromosome number differs.
B. Their proteomes are different.
C. They have slightly different genomes.
D. They express different chromosomes.
B. Their proteomes are different.
Asexual organisms reproduce due to meiosis or mitosis? Explain.
Asexual organisms reproduce primarily through mitosis (or binary fission in bacteria, which is a similar process). Identical copy of DNA.