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
s344n2d4d5 [400]
3 years ago
7

Leaves have air spaces to allow for carbon dioxide and oxygen to move into and out of cells for photosynthesis, which causes wat

er to evaporate and creates greater tension on the mesophyll cells. How do xylem vessels and tracheids prevent collapse in these conditions?
a. Photosynthesis is reversed at times to bring together oxygen and hydrogen ions
b. Metabolic dehydration reactions provide excess water to replace it
c. The turgor pressure of surrounding cells pushes the mesophyll cells into shape
d. Lignin keeps water flowing through the cells
e. Rings maintain their tubular shape
Biology
1 answer:
geniusboy [140]3 years ago
6 0

Answer:

They have  helical thickening of lignin in their walls to prevent collapse

Explanation:

the primary function of Xylem and its conducting vessels tracheids is to provide  support and tranport  water and  minerals  in plants.

Xylem vessels  have layers of dead materials in the walls called LIGNIN.   Lignin is a polymer; a  very strong, hard materials that stop water passage  through it,because it contains dead cells,

Therefore  the presence of  deposit of these strong  impermeable, ligified  walls  in its  walls  prevent its collapse during mass flow of water of transpiration pull.

You might be interested in
This diagram shows the menstrual cycle.
LiRa [457]

Answer:

According to the hormone diagram of the menstrual cycle, the woman is not pregnant due to the behavior of progesterone and estrogens, whose levels do not increase, in addition to the absence of human chorionic gonadotropin.

Explanation:

The graph shows the behavior of hormones during a woman's menstrual cycle in the absence of pregnancy.

During a woman's normal cycle, estrogen, luteinizing hormone (LH) and follicle stimulating hormone (FSH) tend to increase prior to ovulation, reach their peak values at ovulation, and then decline, as shown in the graph. Progesterone, on the other hand, increases after ovulation and decreases if the woman does not become pregnant.

In the case of a pregnant woman:

  • <u>Estrogens</u> continue to increase after ovulation, produced by the ovaries and placenta.
  • <u>Progesterone</u> also increases its levels, as it is a hormone produced by the ovaries and placenta.
  • <u>Hormone human chorionic gonadotropin</u> (HCG) appears and increases during pregnancy, due to the secretory activity of the placenta.

<em><u>The diagram represents the normal cycle of a woman who is not pregnant</u></em>.

4 0
3 years ago
Under the leadership of Mikhail Gorbachev, the doctrine of perestroika called for which of the following?
andreev551 [17]
Under the leadership of Mikhail Gorbachev, the doctrine of perestroika called for "<span>A. Openness in communication", since the "closed off" Soviet Tactics of the past were clearly not working by the 1980s.</span>
5 0
3 years ago
If the sympathetic nervous system prepares your body for ____________, the parasympathetic nervous system prepares your body for
lesantik [10]
The closest answer is C

The sympathetic nervous system is the part of the autonomic nervous system that prepares the body to react to stresses such as threat or injury.

The parasympathetic nervous system is the part of the autonomic nervous system that controls functions of the body at rest.
5 0
3 years ago
Read 2 more answers
1) You can feel a vehicle's side-to-side balance, called its A) roll. B) pitch. C) yaw. D) stability.
attashe74 [19]
1) When a person can feel their vehicle's side-to-side balance it is called a roll. 

2) A humans visual system consists of the retina, brain, and the optic nerve. 
5 0
3 years ago
During the rock cycle what follows erosion? a. Burial, b. Deposition, c. Ingenious rocks, d. Crystallization ,
kakasveta [241]
B. After a rock is moved by deposition it has to be set down by deposition or it needs to be deposited is another way to think of it.
4 0
3 years ago
Read 2 more answers
Other questions:
  • What evidence do scientists use to support theories about climate changes that occured on earth​
    14·2 answers
  • during some kinds of population growth the size of each generation of offspring is larger than the generation before it so as th
    8·1 answer
  • Im playing football and my head is starting to hurt is this a sign of a cuncussion
    12·2 answers
  • Which domain is composed of unicellular prokaryotes that have cell walls that do not contain peptidogcylan
    5·1 answer
  • What is the primary distinction of being an animal?
    15·1 answer
  • Which type of mutation is shown here?
    9·1 answer
  • Is the following statement TRUE or FALSE?
    10·2 answers
  • Banded iron formations show us when
    5·1 answer
  • Cuantos electrones se necesitan para formar una carga de-38 uC sabiendo que la carga de un solo electrón es -1.6x10-19 C​
    6·1 answer
  • I hope you can help me &lt;3
    15·2 answers
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!