Blood pressure(BP) 
Note- Only xylem parenchyma are living cells.
* The ascent of sap is largely favored by diffusion, osmosis and
transpiration processes.
-> The ratio of systolic pressure to diastolic pressure is called
Blood pressure.
* Average BP of a healthy person (adult) is 120/80 mm of Hg
and the instrument which is used to measure BP is called
Sphygmomanometer.
↓
Transportation in Plants
* Important needs of plant:-
Water- from the soil through root hairs
Food- in leaves by photosynthesis
-> Vascular bundles (xylem and phloem) facilitate transportation
in plants.
Note- The energy need by a plant is quite less than the energy
need by an animal because a plant is immobile in nature. So, the transportation system of the plant is a little slower than that of
humans or animals.
Xylem
-> Xylem is a vascular tissue that transports water and
minerals absorbed by the root from soil to all the parts of the
plants.
The phenomenon of upward movement of water and
minerals from the root to aerial part is termed as Ascent of Sap.
↓
Rise
* Xylem has four types of cells-
i)
Xylem fibres
ii) Xylem parenchyma
iii) Tracheids
iv) Vessels
Phloem
-> Phloem is a vascular tissue that transports food from
leaves to different parts of the plant.
The phenomenon of transport of food from leaves to
other parts of the plant are called Translocation.
* Phloem has also four types of cells-
i)
sieve tubes
ii) companion cells
iii) phloem parenchyma
iv) phloem fibres
Note- Only Phloem fibers are living cells.
Ascent of Sap
-> It is made up of four types of cells of Xylem.
* Xylem parenchyma- The main purpose is to store food.
* Xylem fibers- They are used for structural strength or
support.
* Tracheids and vessels- The tabular structures which
conduct water and minerals vertically in plants are called
tracheids and vessels.
* Pits- Pores structure found in tracheids and vessels are
called pits.
Note
-> In the case of flowering plants, both are used for conduction
but In the case of non-flowering plants, only tracheids conduct
water and minerals.
Q) How ascent of sap occur in plants?
Ans- Water & Minerals present in the soil
↓
Root hairs
↓
Xylem vessels of roots
↓
Xylem of stem
Leaf veins
* Vein is made up of a vascular bundle. So, leaf veins are the
vascular tissue of the leaf.
Explanation
- Water and minerals present in the soil. So, the concentration of
water and minerals is higher in soil than in the plant. As a result, the water and minerals get absorbed by the root hairs of the plant.
The xylem present in roots carry the absorbed water and
minerals from root hairs to stem and then the xylem present
in stem carry that absorb water and minerals from stem to
leaves of the plant. In this process, 1% to 2% of water is used
in photosynthesis and the remaining water is lost by plants by
using the
transpiration process.
↓
(The process by which water is lost in the form of water vapor
from the aerial parts of the plant is called transpiration).
- Evaporation of water molecules from the cells of the leaves
create a suction force that pulls water (Transpiration pull)
from the soil with the help of xylem vessels.
Translocation
It is made up of:-
* Sieve tubes- The tubular cells with perforated walls are
called Sieve tubes.
* Companion cells- Sieve tubes are accompanied by
companion (friend) cells which regulate metabolic activities of
sieve tubes elements.
Note- Both are used for conduction.
* Phloem parenchyma- It support sieve tubes and also store
compounds like the starch.
* Phloem fibers- They give mechanical support and
strength to the plant.
Note- Phloem conducts food that is prepared during
photosynthesis. It also conducts hormones, amino acids, etc.
which are necessary for plants.
Q) How translocation occurs inside plants?
Ans- The sugar molecule transferred from leaves to phloem tissue
by using energy because the concentration of sugar molecules
inside leaves are less as compared to sugar molecules present in
phloem tissues. So, In this condition, the sugar molecules
move from lower to higher concentration area with the help of
energy.
Due to this, the concentration of sugar molecules
inside the phloem increases rapidly. Now, water moves from the xylem to this part, and the Osmotic pressure of phloem tissue
increases. As a result of this, materials move from phloem
tissue (Higher osmotic pressure) to other tissue (Lower
osmotic pressure) and this actually leads to the process of
translocation.
It means that translocation is mainly governed by the change
in osmotic pressure.
| Xylem | Phloem |
|---|---|
| * Provide unidirectional support i.e. only upward | * Provide bidirectional support i.e. Both upward & downward |
| * Transport water & minerals from the roots to aerial parts of the plants. | * Transport food & nutrition from the leaves to different parts of the plants. |
| * Xylem cells are present more in number. | * Phloem cells are present less in number as compared to xylem cells. |
| Contain two types of conductive tissues i.e. Tracheids & Vessels | * Contain only one type of conductive cell i.e. Sieve elements |
| * Xylem fibers are usually smaller. | * Phloem fibers are usually larger. |
| * Consists of mainly dead cells, only xylem parenchyma is a living cell. | * Consists of many living cells, only phloem fibers are dead cells. |
Lymphatic system
-> A system in which the network of vessels through carrying
lymph from the tissues into the blood is called Lymphatic
system.
Lymph
-> The tissue fluid present in the body cavity inside the human
body is called lymph. It is also called interstitial fluid. It is a
colorless liquid.
-> In an open circulatory system, lymph and blood are mixed
together. they aren’t separated from each other.
In the case of a closed circulatory system, they are separated
from each other by blood vessels. Blood is enclosed in blood
vessels and lymph is present in a body cavity.
Note- Through the pores of blood capillaries, some amount
of plasma, proteins, and drops of blood escape out into the
intercellular spaces and they will together form lymph.
So,
lymph contains less protein as compared to plasma.
-> Lymph provides unidirectional flow from tissues to the heart.
Lymph transport:-
i) Absorbed fats from intestine to blood
ii) Excess fluid from extracellular or intercellular spaces back
to blood
| Blood | Lymph |
|---|---|
| * Red colored liquid | * Colorless liquid |
| * Flows rapidly | * Flows slowly |
| * Bi-directional in nature. | * Uni-directional in nature. |
| * Contain more proteins. | * Contain fewer proteins. |
| * Contain plasma, RBC, WBC, platelets. | * Contain plasma, WBC & lymphocytes. ↓ Cells present in lymph |
* The primary function of the lymphatic system is to transport
lymph, a fluid containing infection-fighting white blood cells,
throughout the body.
Excretion
-> The process of removal of harmful metabolic waste from
the body of an organism is called excretion.
* Waste products- The unwanted and toxic by-products
of metabolism i.e. Urea, Uric acid, Ammonia, excess salts, etc.
are called waste products.
Need for excretion
* To maintain correct ionic balance in the body.
* To maintain the correct amount of water in the body.
* To maintain toxic levels inside the body because the increase of
toxic levels in the body leading to disease.
* Immunity is adversely affected
-> Certain waste and toxic products are formed during the
functioning of body cells. Waste products like urea etc. are
toxic. When these toxic materials are not removed from the
body, they get mixed with blood and can damage the cells of
the body. Hence, it is necessary to remove such poisonous
waste materials from our bodies.
Excretion in plants
* Here, Oxygen is a waste product which is further utilised
during respiration.
* Water is another waste product with its created through
transpiration.
* Plant also excretes in the form of resins, gums, alkaloids like
quinine etc.
* Plant also excreted through leaves or bark which fall-off
later.
From bark- Tannins (used in dyes and inks)
-> Resins are usually mixtures of organic compounds.
-> Quinine is a bitter compound that comes from the bark of
the
cinchona tree (found in South America).
It was originally
developed as a medicine to fight malaria.
-> Natural gums are long chains of sugars within native
plant materials that are either water-soluble or capable of
absorbing water. Gums are only partially digested by humans
and typically have few adverse side effects.
Excretion in human beings
It consists of:-
* A pair of kidney
* A pair of ureters
* Urinary bladder
* Urethra
* A pair of kidney
-> Located in the abdomen
-> Two kidneys present one on either side of the backbone
-> Bean shaped like structure
-> Notch on the inner concave side present in the kidneys
called ‘Hilum’.
Function- To remove waste
products and excess fluid from the body.
* A pair of ureters
-> Cylinder tubes arising from the hilum of the kidney
-> Opens into the urinary bladder
Function- To carry the urine from the kidney to the urinary bladder.
* Urinary bladder
-> Pear-shaped structure
-> also termed as muscular reservoir of urine
-> Opens in urethra
Function- To store the urine until the
pressure increases.
* Urethra
-> Opens to outside through urethral aperture
-> Longer in males as compared to females
Function- To transport urine from the
bladder to the exterior of the body during urination.
Q) How does excretion happen in human beings?
Ans-> The kidneys remove the nitrogenous wastes such as
urea, salts, and excess water in the form of urine from the
blood. This is done with the help of millions of nephrons
present in the kidney. The waste product moves from the kidneys
to the urinary bladder with the help of a cylindrical tube-like structure
called Ureters.
Now, waste products reach the urethra and
finally excreted from the
human body.
Note- The main purpose of the excretory system is to remove
wastage like urea, uric acid, sweat, etc. from the blood.
Filtration occurs in the kidneys. The basic filtration unit of the kidney is
called the nephron.
Each kidney has many nephrons packed
together.
* Arteriole- A small branch of an artery that leads to a
capillary. The oxygenated hemoglobin (oxyhemoglobin)
makes the blood in arterioles (and arteries) look bright red.
* The afferent arteriole is the arteriole that brings blood to
the glomerulus
and The efferent arteriole is the arteriole
that carries blood away from the glomerulus.
↓
The very thin-walled blood
capillaries arise from arteries that bring blood that contains
waste materials and excess water from different parts of the body called the glomerulus.
-> A nephron consists of:-
* Very thin-walled blood capillaries (Glomerulus)
* Bowman’s Capsule- Each capillary is associated with a cup-shaped end of a tube that collects the filtrated urine and then
transfers to Collecting ducts.
↓
Collect the urine and transfer it
to ureters
Dialysis
-> People with failed or damaged kidneys may have the difficulty of eliminating wastage and excess water from the blood.
Dialysis is an artificial way to carry out this process.
Note- It substitutes the natural work of kidneys. So, it is also
known as Renal Replacement Therapy (RRT).
Explanation
-> In this process the bad blood (blood contain wastage)
comes from the birthday from an arterial line through a flexible
tube called a catheter and goes into the artificial kidney
machine. Now the blood gets filtered in the dialyzer by
a semi-permeable membrane that is made of cellulose or PVC.
The filtered blood then returns to the patient via venal line
through another catheter.
* Haemodialysis is usually done 3 times a week for 3 to 4
hours a day.
* Higher concentration area is blood and lower concentration
area is dialysis solution i.e. bicarbonate solution and water.
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