please guys need your help
Attachments:
Answers
Answered by
0
10... Answer ..
There are a number of differences between veins and arteries.
Veins:
1.carry blood from the tissues of the body back to the heart
2.are usually positioned closer beneath the surface of the skin
3.are less muscular than arteries, but contain valves to help keep blood flowing in the right direction, usually toward the heart
5..would collapse if blood flow stops.
Arteries:
1 . carry blood away from the heart to the tissues of the body
2 ... are usually positioned deeper within the body
... are more muscular than veins
, 3 ... which helps intransporting blood that is full of oxygen efficiently to the tissues
4 ... would generally remain open if blood flow stopped, due to their thick muscular layer.
11. Answer
(a) Mendel demonstrated that traits can be either dominant or recessive through his monohybrid cross. He crossed true-breeding tall (TT) and dwarf (tt) pea plants. The seeds formed after fertilisation were grown and the plants that were formed represent the first filial or F1 generation. All the F1 plants obtained were tall. Then, Mendel self-pollinated the F1 plants and observed that all plants obtained in the F2 generation were not tall. Instead, one-fourth of the F2 plants were short. From this experiment, Mendel concluded that the F1 tall plants were not true breeding; they were carrying traits of both short height and tall height. They appeared tall only because the tall trait was dominant over the dwarf trait. This shows that traits may be dominant or recessive.
(b) Mendel demonstrated that traits are inherited independently through his dihybrid cross. He considered two traits at a time, seed colour and seed shape in which yellow colour (YY) and round shape (RR) are dominant over green colour (yy) and wrinkled shape (rr), respectively. Mendel observed that the F2 progeny of dihybrid cross had a phenotypic ratio of 9 : 3 : 3 : 1 and produced nine plants with round yellow seeds, three plants with round green seeds, three plants with wrinkled yellow seeds and one plant with wrinkled green seeds. In this experiment, he found that round yellow and wrinkled green are parental combinations whereas round green and wrinkled yellow are new combinations. In a dihybrid cross between two plants having round yellow (RRYY) and wrinkled green seeds (rryy), four types of gametes (RY, Ry, rY, ry ) are produced. Each of these gametes segregate independently of each other and each has a frequency of 25% of the total gametes produced. From this experiment, he concluded that when two pairs of traits are combined together in a hybrid, one pair of character segregates independent of the other pair of character. This is known as the law of independent assortment.
Sorry friends ....
18...ANSWER
ii....Medulla oblongata. ... The medulla oblongata helps regulate breathing, heart and blood vessel function, digestion, sneezing, and swallowing. This part of the brain is a center for respiration and circulation. Sensory and motor neurons (nerve cells) from the forebrain and midbrain travel through the medulla.
The cerebellum receives information from the sensory systems, the spinal cord, and other parts of the brain and then regulates motor movements. The cerebellum coordinates voluntary movements such as posture, balance, coordination, and speech, resulting in smooth and balanced muscular activity.
iii...The function of the
Medulla oblongata : controls involuntary actions.
Cerebellum : Coordinates body movement and posture.
Hypothalamus : controls endocrine system and emotions.
Mid brain : Connects forebrain to hindbrain and spinal cord ; controls eye adjustments.
Cerebral hemisphere : controls learning,speech memory,emotion and thought,response to pain and temperature,and the senses..
Pituitary gland : controls growth.
Spinal cord : relays message from the brain to everypart of the body and viceversa.
There are a number of differences between veins and arteries.
Veins:
1.carry blood from the tissues of the body back to the heart
2.are usually positioned closer beneath the surface of the skin
3.are less muscular than arteries, but contain valves to help keep blood flowing in the right direction, usually toward the heart
5..would collapse if blood flow stops.
Arteries:
1 . carry blood away from the heart to the tissues of the body
2 ... are usually positioned deeper within the body
... are more muscular than veins
, 3 ... which helps intransporting blood that is full of oxygen efficiently to the tissues
4 ... would generally remain open if blood flow stopped, due to their thick muscular layer.
11. Answer
(a) Mendel demonstrated that traits can be either dominant or recessive through his monohybrid cross. He crossed true-breeding tall (TT) and dwarf (tt) pea plants. The seeds formed after fertilisation were grown and the plants that were formed represent the first filial or F1 generation. All the F1 plants obtained were tall. Then, Mendel self-pollinated the F1 plants and observed that all plants obtained in the F2 generation were not tall. Instead, one-fourth of the F2 plants were short. From this experiment, Mendel concluded that the F1 tall plants were not true breeding; they were carrying traits of both short height and tall height. They appeared tall only because the tall trait was dominant over the dwarf trait. This shows that traits may be dominant or recessive.
(b) Mendel demonstrated that traits are inherited independently through his dihybrid cross. He considered two traits at a time, seed colour and seed shape in which yellow colour (YY) and round shape (RR) are dominant over green colour (yy) and wrinkled shape (rr), respectively. Mendel observed that the F2 progeny of dihybrid cross had a phenotypic ratio of 9 : 3 : 3 : 1 and produced nine plants with round yellow seeds, three plants with round green seeds, three plants with wrinkled yellow seeds and one plant with wrinkled green seeds. In this experiment, he found that round yellow and wrinkled green are parental combinations whereas round green and wrinkled yellow are new combinations. In a dihybrid cross between two plants having round yellow (RRYY) and wrinkled green seeds (rryy), four types of gametes (RY, Ry, rY, ry ) are produced. Each of these gametes segregate independently of each other and each has a frequency of 25% of the total gametes produced. From this experiment, he concluded that when two pairs of traits are combined together in a hybrid, one pair of character segregates independent of the other pair of character. This is known as the law of independent assortment.
Sorry friends ....
18...ANSWER
ii....Medulla oblongata. ... The medulla oblongata helps regulate breathing, heart and blood vessel function, digestion, sneezing, and swallowing. This part of the brain is a center for respiration and circulation. Sensory and motor neurons (nerve cells) from the forebrain and midbrain travel through the medulla.
The cerebellum receives information from the sensory systems, the spinal cord, and other parts of the brain and then regulates motor movements. The cerebellum coordinates voluntary movements such as posture, balance, coordination, and speech, resulting in smooth and balanced muscular activity.
iii...The function of the
Medulla oblongata : controls involuntary actions.
Cerebellum : Coordinates body movement and posture.
Hypothalamus : controls endocrine system and emotions.
Mid brain : Connects forebrain to hindbrain and spinal cord ; controls eye adjustments.
Cerebral hemisphere : controls learning,speech memory,emotion and thought,response to pain and temperature,and the senses..
Pituitary gland : controls growth.
Spinal cord : relays message from the brain to everypart of the body and viceversa.
Attachments:
dhananjay2345:
sorry
mate
please select brainlist
sorry
i don't have
select brainlist
Answered by
1
12) Rohit focused the image of a candle flame on a white screen using a convex lens. He noted down the position of the candle , screen and lens as under : Position of candle = 26.0 cm Position of convex lens = 50.0 cm Position of screen = 74.0 cm i) What is the focal length of the convex lens? ii) Where will the image be formed if he shifts the candle towards the lens at a position of 38 cm? iii) Draw a ray diagram to show the formation of the image in case (ii) as said above?
A) Digram is in the first image
Position of candle = 26cm
Position of convex lens = 50cm
Position of screen = 74cm
(i) object (candle ) distance from lens , u = 50cm - 26cm = 24cm
image (on screen) distance from lens ,v = 74cm - 50cm = 24cm
Here , v = u
it means object place at centre of curvature of lens
so, u = 2f , f is focal length
f = u/2 = 24/2 = 12cm
(ii) position of candle = 38cm
so, object (candle ) distance from convex lens = position of convex lens - position of candle = 50cm - 38cm = 12cm
∴ u = -12cm and focal length f = 12cm
Now, use formula,
1/f = 1/v - 1/u
1/12 = 1/v -1/-12
⇒ v = ∞ , hence image is formed at infinity .
Three examples are
13). a. The pH of soil plays an important role in the growth of plants. Plants grow well in specific pH range.
b. In our stomach pH should be maintained. Decreased pH value increases acidic nature and we suffer from a condition called acidity.
c. Water bodies should have constant pH range, as any changes in this range will affect aquatic life.
OR
Plaster of paris.
it is used in hospitals for fixing fractures,supporting the bones in right position.
Equation - CaSO4.1/2H2O + 1 1/2H2O ---------> CaSO4.2H2O
calcium sulphate hemihydrate gypsum
14)
Fossils are the impressions or remains of the dead organisms which are found in our remote past. They help in determining the evolutionary relationships among organisms. For example - Archaeopteryx, a fossil bird has some features similar to birds and some to reptiles which prove that birds might have evolved from reptiles. The fossils which are found in deeper layers of the surface of the earth are more ancient organisms as compared to the ones found on the upper layers. The two ways of determining the age of fossils are:
a. By dating: Where isotope of Carbon (C14), uranium, potassium or argon is used to determine the age of fossils.
b. Relative method: The fossils which are found closer to earth's surface are more recent as compared to fossils which are found in deeper layers.
15) A)sexually transmitted disease and viral disease.caused by human immunodefeciency virus
B)awareness,rational thought
16) Magnetic Field around a straight wire current carrying conductor will be concentric circles.
1)Rule that is used to find the direction of magnetic filed is Right Hand thumb rule . which states that " If you hold a current carrying conductor in our hand , if thumb indicates the direction of current then four fingers curled direction will be the direction of magnetic field."
Please see the attachment for the diagram.
2)Yes similar magnetic field will be observed around a thin beam of moving
(α) alpha particles as they are positively charged particles.
3) Neutrons will not produce any pattern of magnetic field as they do not have charge.
17 ) There are three ways to join the models of six carbon atoms and fourteen hydrogen atoms to form different molecules of C6H14
First way is straight chain of carbon atoms
Second way is branched chain of carbon atoms
Third way is closed chain of carbon atoms.
Isomers of C6H14 are shown below. We can arrange the number of C atoms as follows:
Hexane
2-methyl pentane
3-methyl pentane
2,2-dimethylbutane
2,3-dimethyl butane
Attachments:
Done
Similar questions