Answer:
Chitinous exoskeleton and segmented bodies.
Explanation:
Phylum Arthropoda are known as jointed legs species which include crabs, spiders, ants, etc. The important characteristic of Arthropoda is they have a hard chitinous exoskeleton that provides them protection and gives flexibility. These phylum species can survive in both terrestrial and marine habitats. Some characteristics of phylum Arthropoda are given below:
1) They have Chitinous exoskeleton which is hardened.
2) Their digestive tract is present at opposite ends of the body and complete with the mouth and anus.
3) They contain jointed limbs.
4) The body structure of these species is showing bilateral symmetry.
Force required = F = ?
mass of the car = m = 1200 kg
initial velocity of the car = Vi = 10 m/sec
final velocity of the car = 0
time required to stop the car = t = 20 sec
Using Newton`s 2nd law of motion;
F = ma ………………………(1)
as a = Vf - Vi / t , put this value in equation (1)
F = m ( Vf - Vi /t ) ………………(2)
F = 1200 ( 0 - 10 /20) = - 600 N
here Negative sign shows that external force is acting in opposite direction of the motion to bring it to rest.
we can also calculate this force by using the relation
Rate of change of momentum = net force acting on the object …………(3)
m Vf - m Vi / t = net force acting on the object
m (Vf - Vi / t) = F
1200 ( 0 - 10 /20) = - 600 N = F
so, net force acting on the object =F = - 600 N
Answer: Skeletal Muscle
Explanation:
Skeletal muscle is a form of "striated" (striped) muscle tissue. It is under the voluntary control of the somatic nervous system. Most skeletal muscles are attached to bones by bundles of collagen fibers known as tendons.
I will answer the question accordingly so that it help you under stand it better.
Question A.
During an extreme heat wave, plants with white flowers survive better.
What mechanism is in work here?
Answer: Mechanism of Natural Selection
will work here. This is called survival of the fittest which means the best color which fits in harsh conditions will dominate over others and will survive for longer time.
What is the effect on the gene pool?
Answer: The Frequency of white allele will increases
because white color is the best fit to extreme heat wave.
Question B.
A person uproots the five closest plants, which all happen to have white flowers.
What mechanism is in work here?
Answer: The mechanism of gene flow will work here as color of flower represents genotype of flower.
What is the effect on the gene pool?
Answer: The Frequency of white allele will increases because genotype of white flowers is increased.
Answer:
Image result for Which scientists determined that cells come only from other cells ?
Cell theory was eventually formulated in 1839. This is usually credited to Matthias Schleiden and Theodor Schwann. However, many other scientists like Rudolf Virchow contributed to the theory.
Explanation:
hope this helps
