Signaling
Neurotransmitters located at what type of signaling?
Synaptic Signaling
Internal receptors are found in _______ and respond to ___________(hydrophobic/hydrophilic) ligand
Internal receptors are found in cytoplasm and respond to hydrophobic ligand
What is the longest phase of the cell cycle?
Interphase
Sexual reproduction requires more energy and resource, what’s the advantage then?
It increases genetic diversity and can help us cope with environmental changes.
What'd the function of cyclins and cyclin-dependent kinases (Cdks )?
responsible for the progress of the cell through the various checkpoints
What two types of Local Signaling are found in multicellular animals?
Paracrine and Synaptic signaling
Ion channel-linked receptors control the flow of ions within the cell ion channels impregnation receptors responsible for conversion of the ________ signal into an_________one.
Ion channel-linked receptors control the flow of ions within the cell ion channels impregnation receptors responsible for conversion of the chemical signal into an electrical one
What are the differences between mitosis division in plants cell and animals cell?
Cell plate that divides cytoplasm in plants but not animals
True/False: A diploid parent cell is haploid after telophase I.
why?
True. Meiosis I reduces chromosome number in half. It stays the same through Meiosis II.
Which type of signaling has slower response but have a longer- lasting effect?
Endocrine Signaling
What are signaling molecules called at direct Signaling Across Gap Junctions? What about Endocrine Signaling?
- Intracellular Mediators
- Hormones
What is dimerization of receptor?
two receptors bind to each other to form a stable complex
Attachment of the mitotic spindle fibers to kinetochores is charact of which stage of mitosis?
prometaphase
During meiosis I,
a. Homologous chromosomes separate.
b. Each sister chromatid becomes a chromosome.
c. Sister chromatids separate.
d. 4 daughter cells are formed from a single original cell
A
What are negative regulators of the cell cycle? (3)
-Retinoblastoma protein (Rb),
-p53
-p21
What initiates signal and what are steps of signal transduction in details?
Binding of ligand.
In G-protein-linked receptors resultant shape change releases__________(ATP/GTP/GDP/ADP)
resultant shape change releases GDP
What structure produces spindle fibers to separate the sister chromatids?
Centrioles
Chromosome A contains genes for an eye color of hazel. Chromosome B contains genes for hair color of hazel, and chromosome C contains genes for an eye color of blue. Which chromosomes are homologous?
A and C, both for eye color
Which eukaryotic cell cycle event is missing in binary fission? Why?
DNA duplication
cell growth
karyokinesis
cytokinesis
karyokinesis is splitting of cell's nucleus during mitosis and binary fission involves prokaryotes that don't have a nucleus
What are some examples of when autocrine signaling occurs?
-during the early development of an organism to ensure that cells develop into the correct tissues
-regulates pain sensation and inflammatory responses
The receptors for a group of signaling molecules known as growth factors are often_________
receptor tyrosine kinases
If the M checkpoint is not cleared, what stage of mitosis will be blocked? Why?
Anaphase.
M checkpoint checks for chromosome spindle attachment and occurs after metaphase, as prophase and prometaphase are initial stages that don't have checkpoints. At anaphase stage the separation of sister chromatids occurs. If the spindles not correctly attached to the kinetochore, M checkpoint won't allow cycle to proceed.
If a normal diploid cell has 8 chromosomes, then
a. there are 8 homologous pairs of chromosomes per diploid cell
b. there are 8 chromatids per diploid cell between S phase and the first division of meiosis
c. there are 4 chromosomes per cell after meiosis I
d. sperm cells made from this diploid cell would have 8 chromosomes
e. There is more than one answer
C. Meiosis I divides chromosome number in half.
What do p53 and Rb do?
-If damaged DNA is detected, p53 halts the cell cycle and recruits enzymes to repair the DNA (if cannot be repaired, p53 can trigger apoptosis)
-Rb monitors cell size and prevents the G1/S transition