Answer: Single cell organisms dont need a respiratory system because oxygen and carbon-dioxe diffuses between their body tissues and the enviorment.
Answer:
D. Molecules called pumps function to control active transport.
Explanation:
Active transport is one of the two types of transport (the other being passive transport). It is the type of transport in which substances move against their concentration gradient i.e. from a lower concentration to a higher concentration. Hence, due to this, energy input in form of ATP is required by the cell.
However, the process of active transport makes use of certain molecules called PUMPS to control it. The pumps moves ions/molecules against their concentration gradient. An example is the sodium-pottasium pump which moves sodium ions from a region of low conc. to a region of high conc.
C. Rashelle needs more than the usual number of drinks to feel high
The correct option is A.
Horse are herbivores, they eat plants. Large amount of the digestion and absorption of these plant materials occur in the cecum. Horses have enlarged cecum which helps in the digestion process of their food.
Answer:
Chromosomes (two sister chromatid bonded) or Chromatids (separate parts of a chromosome)