The male
human has a sperm cell and the female has an egg cell. The cells from the male
and female that combine to form a zygote are called gametes. The human sperm
and egg cells each contain 23 chromosomes. . A combination of gametes forms a
zygote with 46 chromosomes. The type of cell division that produces gametes
with half the normal chromosome number is the meiosis. Meiosis is the type of
cell division used in sexual reproduction. It will occur in the testes and
ovaries.
Lasts are used for photosynthesis .
They have a double membrane around them.
The space inside is called the stroma. The space may contain starch grains and lipid bodies.
In the stroma are structures called thylakoids.
The thylakoids are stacked to form structures called grana.
The grana contain the pigment chlorophyll along with some secondary pigments.
Answer:
Between 120 and 170.
Explanation:
Earthworm belongs to membrane of phylum Annelida. Membrane of this phylum shows the bilateral symmetry, containing a rudimentary head region, and have segmented bodies.
An adult earthworm has approximately more than 120-170 segments on their bodies, which is known as annuli. They are hermaphrodites in nature each having male, and female sex organs. They lack a true skeletal, and maintain their body with fluid-filled coelom chamber which function as a hydrostatic skeletal.
Answer:
Genetic engineering has multiple applications in different fields. Genetic engineering is the process by which alterations are made at the genetic level so that the final product is superior in quality and yield.
Explanation:
Following are few of it's applications:
<u>Medical field</u>- Genetic engineering is been used to produce insulin artificially, human growth hormones, anti hemophiliac factors, vaccines and other drugs.
<u>Agricultural industry</u>- It has been used to synthesize improvised crops which give better yield and are pest resistant. E.g Flavr savr, a species of tomato which is more juicy and larger in size than regular tomatoes.
<u>Environment</u>- With the introduction of herbicide resistant corn, farmers reduced the use of tractors which in turn reduced the amount of greenhouse gases. Also, by imparting disease resistance to plants, a lot of plants are prevented from dying. In addition, the biodiversity of an area can be maintained.