Answer:
When the meteor hit a caused a chain reaction which caused all that and made some cloud that was toxic.
Explanation:
Answer:b
Explanation:some seeds do not germinate during adverse conditions.this is called dormancy.this may occur due to hard seed coat.this seed coat prevents the entry of water and oxygen which are necessary for the plant to grow and germinate.
Water is a nessesary medium for essential metabolic reactions in the seed.the temperature at which is seed would germinate also varies.
Oxygen is needed for a germinating plant to obtain energy through respiration. The seed coat may also be so tough that they resist growth and expansion from taking place.
Seeds are able to break dormancy on their own.some may need to undergo natural processes that lead to softening.this process may be slow.some others may need heat or certain nutrients.
Germination of seed occurs when the dormant plant has taken in water and oxygen to show high metabolic activities leading to the formation of a seedling.
Continuous conduction takes place in unmyelinated axon.
Explanation:
Based on the presence and absence of myelin sheath, the neurons had been classified as myelinated and non-myelinated neurons respectively.
In myelinated neurons the transmission of impulse takes place only at the non myelinated region called nodes of Ranvier. Due to this, the conduction in Myelinated neuron is saltatory.
The conduction in non-myelinated neuron takes place throughout the length of axon and it is continuous.
Saltatory conduction is faster than continuous conduction.
Answer and explanation;
Nucleus; houses a cell's DNA and its processes include protein, replication and packaging for cell division. It is also the site for transcription.
Cytosol; coordinates a responsible to the environment, metabolism and motor proteins.
Endomembrane system; includes the nuclear envelope (surrounds nucleus), rough and smooth ER, golgi body, lysosomes?vacuoles, peroxisome and plasma membrane.
Semiautonomous organelles; mitochondria (animals) and chloroplast (plants) which provide energy for the cell.
D.hot air rising and cooler air falling. A is example of radiation or conduction. B is example of radiation. C is example of conduction. D is example of convection