Answer:
Monocercomonoides isn’t a living fossil, a holdout from the days of the earliest eukaryotes, Karnkowska notes. Its closest relatives still have small mitochondria, suggesting that it jettisoned the organelles fairly recently in evolutionary terms. She and her colleagues speculate that more eukaryotes missing mitochondria await discovery.
Explanation:
<h2>Action potential </h2>
Explanation:
Brief sequential change in the membrane potential of excitable cells after stimulus is called action potential
Phases of action potential includes:
- Depolarization: Starts when a threshold stimulus applied on a neuron via Na+ mechanically operated channels that trigger action potential
- Depolarization of membrane potential is due to influx of Na+ via voltage gated Na+ channels
- Fast opening of voltage gated Na+ channels shift membrane potential from -70mV to +50mV at which voltage gated Na+ channels becomes inactive, thus influx of Na+ abruptly stops
- Repolarization: Starts with the efflux of K+ by the opening of voltage gated K+ channels
- Voltage gated K+ channels starts to open when voltage gated Na+ channels becomes inactive
- Hyperpolarization: Occurs due to excessive efflux of K+ by voltage gated K+ channels
- Additional efflux of K+ occurs due to slow inactivation of voltage gated K+ channels
- In a typical neuron cell, membrane potential of cytoplasm is negative (-70mV) at rest hence called resting membrane potential
- Resting membrane potential of excitable cells is established by Na+ K+ pump and maintained by K+ leaky channels at rest
Answer:
It's B. Nucleic acids have the code that determines which proteins are made.
Explanation:
If these are the choices:
Proteins read the instructions that are contained in nucleic acids.
Nucleic acids synthesize the amino acids for protein construction.
Nucleic acids provide the blueprint for the construction of proteins.
Proteins are composed of nucleic acids..
The site above can help. It says that... "Without oxygen, cellular respiration could not occur because oxygen serves as the final electron acceptor in the electron transport system. The electron transport system would therefore not be available. Glycolysis can occur without oxygen. Although glycolysis does not require oxygen, it does require NAD+. Cells without oxygen available need to regenerate NAD+ from NADH so that in the absence of oxygen, at least some ATP can be made by glycolysis