Why can oxygen diffuse across a cell membrane but a protien cannot?
a. oxygen is polar unlike proteins
b. proteins asre blocked by protien channels
c. proteins are smaller than oxygen
d. oxygen is smaller than proteins

Leslie argues that an organism called a Euglena is a plant because it is eukaryotic, has a nucleus, makes its own food, and is unicellular. Where is Leslie's error? Plants do not make their own food..

In school, Brendan has been conditioned to get up from his seat every time he hears the school bell ring.

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Myths about aging : 

Depression and loneliness are normal in older adults. ...

The older I get, the less sleep I need. ...

Older adults can't learn new things. ...

It is inevitable that older people will get dementia. ...

Older adults should take it easy and avoid exercise so they don't get injured.

Explanation: with a great tolerance to a wide range of conditions the species would adapt and thrive which would allow it to reproduce and have all it needs to survive, grow, and take over.

A spring is a natural discharge point of subterranean water at the surface of the ground or directly into the bed of a stream, lake, or sea. Water that emerges at the surface without a perceptible current is called a seep. Wells are holes excavated to bring water and other underground fluids to the surface.

The image shows a cross-section of land scape.

Consumers are dissatisfied with the way that large corporate  farms are treating nature's natural resources.

Rank the following cities in order of earthquake risk from high risk to low risk:

Astronomers are able to detect the dimmer star because its gravity causes the bright star to . Astronomers can also spot the dimmer star by observing a phenomenon called a(n) binary.

Fungi are a food source for animals and humans. Fungi produce oxygen to breathe. Fungi destroy rocks and minerals. Fungi are natural recyclers.