Answer:
In humans and other mammals, biological sex is determined by a pair of sex chromosomes: XY in males and XX in females. Genes on the X chromosome are said to be X-linked. X-linked genes have distinctive inheritance patterns because they are present in different numbers in females (XX) and males (XY).
Explanation:
Turn the revolving turret (2) so that the lowest power objective lens (eg. 4x) is clicked into position.
Place the microscope slide on the stage (6) and fasten it with the stage clips.
Look at the objective lens (3) and the stage from the side and turn the focus knob (4) so the stage moves upward. Move it up as far as it will go without letting the objective touch the coverslip.
Look through the eyepiece (1) and move the focus knob until the image comes into focus.
Adjust the condenser (7) and light intensity for the greatest amount of light.
Move the microscope slide around until the sample is in the centre of the field of view (what you see).
Use the focus knob (4) to place the sample into focus and readjust the condenser (7) and light intensity for the clearest image (with low power objectives you might need to reduce the light intensity or shut the condenser).
When you have a clear image of your sample with the lowest power objective, you can change to the next objective lenses. You might need to readjust the sample into focus and/or readjust the condenser and light intensity. If you cannot focus on your specimen, repeat steps 3 through 5 with the higher power objective lens in place. Do not let the objective lens touch the slide!
When finished, lower the stage, click the low power lens into position and remove the slide.
Your microscope slide should be prepared with a coverslip over the sample to protect the objective lenses if they touch the slide.
Do not touch the glass part of the lenses with your fingers. Use only special lens paper to clean the lenses.
Always keep your microscope covered when not in use.
Always carry a microscope with both hands. Grasp the arm with one hand and place the other hand under the base for support.
To absorb nutrients and help us grow and to get rid of harmful bacteria
Answer:
True
Explanation:
Tobacco is consumed during smoking which contains an addictive substance called Nicotine. Nicotine exerts its effect on the body by stimulating the acetylcholine receptors in the neurons. The stimulation of these receptors stimulates another neurotransmitter like glutamate, dopamine and GABA which produce addictive effects in humans.
Since the acetylcholine is involved in stimulating the other neurotransmitters therefore true is the correct answer.
Thus, true is the correct answer.
The most important physical fitness for your and middle aged
adults is cardiorespiratory endurance as this measures the capability and
health of the heart, muscles and lungs in making sure that they are strong
enough and making the body work enough and to be fit, this is a component in
enhancing a maintaining a good health to an individual.
