Nitrogen and oxygen make up about 99%of the atmosphere. I'm not sure if it will help! But thats all I know.
Answer: These may be:
- physical defenses (1st line)
- chemical defenses (2nd line)
Explanation:
Plants employ several methods in order to defend themselves from pathogens. These may be physical defenses or chemical ones. Several have adaptations to their surfaces that prevent the entry of pathogens, called physical barriers such as
- thick waxy cuticles
- thorns, which are modified plant branches
- spines, which are modified plant leaves
- gall production at infected sites to prevent pathogenic spread
Chemical defenses include the production or secretion of:
- defensins
- antimicrobials such as tannins or resins
- gum at areas facing pathogenic attacks
Answer:
ur answer A is correct i think-
Explanation:
Seminal vesicles
prostate gland
<span>bulbourethral glands
</span>The male reproductive system is designed to make sperm or male gametes and is adapted to provide for the delivery of these gametes to the female to allow for fertilization. It consists of:1. Testes- produces sperm and the hormone testosterone2. Scrotum- pouch enclosing the testes keeping the sperm at an optimum temperature.3. Vas deferens- tube that carries sperm away from the testes.4. Prostate gland- adds lubricating and other fluids to the sperm.5. Urethra- tube through the penis carrying sperm to the outside of the body.<span>6. Penis- adaptation for internal fertilization of the female.</span>
Answer:
This question is all explanation, buddy. Take a read.
Explanation:
To start, you need to have a basic understanding in what chromosomes are. There are 23 pairs of chromosomes (46 total) in each cell. Almost all the other cells in your body have 46 chromosomes. There are two types of cells that are different, however. These are the eggs in a female and the sperm in a male. These sex cells , or gametes, have 23 each.
The sperm passes through the opening of the cervix and travels into the fallopian tubes. There, the sperm will penetrate and fertilize an egg. You'd like to think this is a one on one process, but actially- many sperm cells attempt to try to penetrate the egg but only one makes it in. no more than one, though. Once fertilized, the egg travels down the fallopian tube toward the womb, or uterus, where it will implant in the uterine wall.
During early pregnancy, a female's egg joins with the father's sperm to make a new cell. The cell then will grow and divide into a baby. This first cell has 46 chromosomes, 23 from the mother and 23 from the father. The genes on these chromosomes contain all the instructions for how the child will grow. Each cell of the body will contain exact copies of the 23 pairs of chromosomes that were in the first cell that was formed by the egg and sperm. The determination of which genes the child gets though (aside from essential genetic material) is up to the genetic lottery, however the likelihood of certain genetic traits can be mapped and predicted. Like hair colour, eye colour, etc. But that's an unrelated (to this question, anyway) subject altogether.
I hope that answers your question.
