Biology1202 Exam 2

What types of molecules can pass easily through the membrane?

Small nonpolar molecules (O2+CO2)

What role does cholesterol play in membrane fluidity?

Maintains fluidity and stability

The main function of the membrane is to:

A. Produce Energy

B. Store DNA

C. Control what enters and leaves the cell

D. Make protein

C. Control what enters and leaves the cell

Integral protein:

A. Sit only on the surface

B. Span across the membrane

C. Are made of lipids

D. Are carbs

B. Span across the membrane

What is the main purpose of cell signaling?

A. To produce energy

B. To break down nutrients

C. To allow cells to communicate and respond to their environment

D. To replicate DNA

C. To allow cells to communicate and respond to their environment

Which of the following is NOT one of the three main stages of cell signaling?

A. Reception

B. Digestion

C. Transduction

D. Response

B. Digestion

A signaling molecule that binds to a receptor is called a:

A. Enzyme

B. Ligand

C. Substrate

D. Ion

B. Ligand

Endocrine signaling typically involves:

A. Direct cell contact

B. Only nearby cells

C. Long distance travel through the bloodstream

D. Electrical impulses only

C. Long distance travel through the bloodstream

Signal transduction refers to:

A. Breaking down signal

B. Moving signals out of the cell

C. Creating new cells

D. Converting a signal into a cell response

D. Converting a signal into a cell response

DNA wraps around which structure to form a nucleosome?

A. Ribosome

B. Histome

C. Enzyme

D. Membrane

B. Histome

Chromatin is best described as a:

A. A signal gene

B. DNA+Protein

C. A type of RNA

D. A cell membrane

B. DNA+Protein

Nucleosomes help primarily with:
A. Energy production

B. DNA packaging

C. Protein digestion

D. Cell movement

B. DNA packaging

Chromosomes are formed when chromatin becomes:

A. Broken apart

B. Loosely packed

C. Tightly condensed

D. Dissolved

C. Tightly condensed

Cell signaling helps maintain ______ and allows cells to respond to their _____

homeostasis; environment

The three stages of cell signaling are _____, ______, and _____

reception, transduction, response

DNA wraps around _____ proteins to form ______

histome; nucleosome

Sister chromatids are held together at the ______

centromere

The ____ checkpoint check for DNA damage before DNA replication

G1

The ____ checkpoint ensures DNA is replicated before mitosis begins

G2

The ____ checkpoint ensures chromosomes are properly attached to spindle fibers before separation

M

Hormones typically travel through:
A. Cell Membrane

B. The bloodstream

C. Cytoplasm

D. Ribosomes

B. The bloodstream

What happens during signal transduction:

A. DNA is copied

B. A signal is converted into a cellular response

C. Proteins are broken down

D. Energy is produced

B. A signal is converted into a cellular response

A molecule that binds to a receptor is called a ____.

Ligand

Signals that pass directly through the membrane are usually _______(soluble)

hydrophobic

A researcher observes that a signaling molecule only affects nearby cells and is quickly broken down. Identify type of signaling and its importance.

Paracrine signaling- local, fast, controlled response

What is the main purpose of Mitosis?

A. To produce gametes

B. To create genetic variation

C. To produce identical body cells

D. To reduce chromosome number

C. To produce identical body cells

What structure pulls chromatids apart?

A. Ribosome

B. Spindle Fibers

C. Cell Membrane

D. Mitochondria

B. Spindle Fibers

The phase where chromosome pull apart and become visible is _____

Prophase

The phase where the nuclear membrane reforms is _____

Telophase

Identical copies of each chromosome are called _____

Sister chromatids

The structure that organizes spindle fibers is _____

Centrosome

A cell fails to separate sister chromatids during mitosis. What phase is affected and what will happen to the daughter cells?

Anaphase- the wrong number of chromosomes will be produced

All cells:

A. Contain the same four macromolecules

B. Use energy

C. Don’t reproduce and divide

D. Share different ancestry

A. Contain the same four macromolecules

B. Use energy

Phase: Homologous chromosomes separate

Anaphase

Phase: Chromosomes line up in pairs

Metaphase

Phase: Final stage producing four cells

Telophase II

Phase: Crossing over occurs

Prophase

The pairing of homologous chromosomes is called:

Synapsis

The exchange of genetic material between homologous chromosomes is called:

Crossing over

Cells produced by meiosis are: (hap/dip)

Haploid

The random alignment of chromosomes is called:

Independent Assortment

In this type of inheritance, both alleles are fully expressed

Codominance

A version of a gene

Allele

Trait expressed when present

Dominant

Which example shows environmental influence?

A. Eye color

B. Blood Type

C. Tanning from sunlight

D. DNA replication

C. Tanning from sunlight

What happens in epigenetic?

A. DNA sequence changes

B. Genes are removed

C. Genes are turned on or off

D. Traits disappear

C. Genes are turned on or off

Which factor is an environmental influence?

A. DNA sequence

B. Genes

C. Diet

D. Chromosomes

C. Diet

Why can identical twins be different?

They have the same DNA, but different environments and experiences affect how their traits are expressed