D. All 3..................................
Each population is characterized by a certain percentage of asexual and sexual reproduction. The percentage of asexual reproduction ranges between 0% (complete sexual reproduction) and 100% (all the females reproduce by gynogenesis).
1. The correct answer is B. Conservation tillage practices help the soil erosion and also maintains soil nutrient levels.
Conservation tillage is termed as the tillage system which helps to conserve energy, soil, water through retention of crop residue and reduction of tillage intensity.
2. Correct answer is A. Aquifers 1 and 3 may result in a reduced river flow. Aquifer is termed as the underground layer of rock fractures, water-bearing permeable rock.
Hydrogeology is termed as study of water flow which is found in aquifers.
3. Correct answer is A. Recycling materials helps decrease the amount of new material which are taken from environment.
Most household can be recycled. Some other examples which are recycled include textiles, plastics, organics, and metals. Metals such as drinking bottles and food cans which are made from steel and aluminium can be recycled.
Answer:
System 1 breaks food down into nutrients,
and system 2 transports the nutrients to cells
in the body.
Answer:
Diffusion : Is the movement of molecules / ions from a region of higher to lower concentration. It may or may not occur across a semi permeable membrane.
In diffusion there is no challenge involved as it is along the concentration gradient, but in active transport movement of molecules occur against concentration gradient ie; from lower to higher concentration.
2) For active transport, energy is vital for movement, in this case protein molecules function as molecular pumps to enable the cell accumulate glucose/ions, against concentration gradient. Here metabolic energy ATP is required.
3)Facilitated diffusion is a type of passive transport in which ions/molecules cross the semi permeable membrane because permeases present in the membrane facilitate the transport.
Like simple diffusion facilitated diffusion doesn't require metabolic energy and simply occurs across the concentration gradient.
4) Osmosis : is movement of water from hypotonic solution (lower concentration) to hypertonic solution (higher concentration) through a semi permeable membrane.
The cell membrane being permeable to water allows to and fro movement of water molecules along the concentration gradient.