1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
Simora [160]
3 years ago
14

How do materials move across cell membranes? compare the different transport mechanisms for moving molecules across the plasma m

embrane (e.g. is energy required? are the molecules moving down a concentration gradient or against a concentration gradient?
Biology
1 answer:
Alex777 [14]3 years ago
8 0
There are 3 methods that materials are transported across cell membranes in basic. Diffusion, osmosis and active transport.

In diffusion, the net movement of fluid is from a region of higher concentration to lower concentration, down the concentration gradient , resulting from the random movement of particles. They do not require extra energy and there will be no more net movement when both sides has a equal concentration.

For osmosis, its the net movement of water molecules only from a region of higher water potential to lower, down the concentration gradient, but must be through a semi permeable membrane (cell membrane in this case). Also, it doesn't require extra energy.

And for active transport, it's the movement of particles against the concentration gradient, by using extra energy provide from for example cellular respiration. It also requires protein carriers.
You might be interested in
Some reptiles, like snakes, have olfactory receptors (smell) _____.
tankabanditka [31]
I think the correct answer would be the second option. Some reptiles, like snakes, have olfactory receptors (smell) on the roof of their mouths. As we can observe, snakes usually flick their tongues. This action is made so that they would collect substances from the ground or the air. Their tounges do not have the receptors for smell and taste rather it is located in the roof of the mouth or the vomeronasal. As the tongue goes inside the mouth of the snake, it is being received by the receptors in the mouth and would transmit a number of signals to the brain. The tongue simply deposit the substances that was collected onto the mouth.
8 0
3 years ago
The graph shows the carrying capacities for two populations of salmon in two different areas which statement is most likely true
nika2105 [10]

The most likely answer is that there is more food in salmon A location

Hope this helps!

6 0
3 years ago
Read 2 more answers
What fraction of the offspring of parents each with the genotype k/k l/l m/m will be k/k l/l m/m?
Ainat [17]
I don't even know the answer sorry
4 0
3 years ago
Why cycus are called conifer? give its 3major characteristics features​
Licemer1 [7]

Answer:

Cycads /ˈsaɪkædz/ are seed plants that typically have a stout and woody (ligneous) trunk with a crown of large, hard, stiff, evergreen and (usually) pinnate leaves. The species are dioecious, therefore the individual plants of a species are either male or female. Cycads vary in size from having trunks only a few centimeters to several meters tall. They typically grow very slowly[3] and live very long, with some specimens known to be as much as 1,000 years old.[citation needed] Because of their superficial resemblance, they are sometimes mistaken for palms or ferns, but they are not closely related to either group.

Cycads are gymnosperms (naked seeded), meaning their unfertilized seeds are open to the air to be directly fertilized by pollination, as contrasted with angiosperms, which have enclosed seeds with more complex fertilization arrangements. Cycads have very specialized pollinators, usually a specific species of beetle. Both male and female cycads bear cones (strobili), somewhat similar to conifer cones.

Cycads have been reported to fix nitrogen in association with various cyanobacteria living in the roots (the "coralloid" roots).[4] These photosynthetic bacteria produce a neurotoxin called BMAA that is found in the seeds of cycads. This neurotoxin may enter a human food chain as the cycad seeds may be eaten directly as a source of flour by humans or by wild or feral animals such as bats, and humans may eat these animals. It is hypothesized that this is a source of some neurological diseases in humans.[5][6]

Cycads all over the world are in decline, with four species on the brink of extinction and seven species having fewer than 100 plants left in the wild.[7] The plant has a very long fossil history, with evidence that they existed in greater abundance and in greater diversity before the Jurassic and late Triassic mass extinction events.

Explanation:

~Dr.Smiley~

(Jane)

8 0
2 years ago
Air helps protect living things from harmful ________
LUCKY_DIMON [66]
The answer would have to be radiation because the air cools us off most times by moving around the radiation to cool it off. If there was no air to cool of the radiation from the sun, we would burn up, but then of course there are atmospheres.
5 0
3 years ago
Other questions:
  • What can happen when you have taken much more than the normal amounts of vitamins?
    11·2 answers
  • Name all material students use at the lab station?
    6·1 answer
  • What are the two major abiotic factors that determine terrestrial biomes?​
    6·1 answer
  • Cystic fibrosis is a genetic disorder in homozygous recessives that causes death during the teenage years. If 9 in 10,000 newbor
    9·1 answer
  • Why might it be important to the survival of a species that mutations to dna cause changes in organisms?
    14·1 answer
  • The presence of many C-C and C-H bonds causes fats to be ... The presence of many C-C and C-H bonds causes fats to be ... (a) ri
    10·1 answer
  • Total Pieces of Food Eaten 57 153 90 Food Percentage* 19 % 51 % 3 % Simulated Number of Birds in Flock for 2nd Generation**
    12·1 answer
  • What's the meaning of DNA​
    5·1 answer
  • Explain the process in which sedimentary rocks form
    9·2 answers
  • Beth broke her ankle bone. The doctor
    14·2 answers
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!