Explanation:
Fertilization, pictured in Figure 24.23a is the process in which gametes (an egg and sperm) fuse to form a zygote. The egg and sperm each contain one set of chromosomes. To ensure that the offspring has only one complete diploid set of chromosomes, only one sperm must fuse with one egg. In mammals, the egg is protected by a layer of extracellular matrix consisting mainly of glycoproteins called the zona pellucida. When a sperm binds to the zona pellucida, a series of biochemical events, called the acrosomal reactions, take place. In placental mammals, the acrosome contains digestive enzymes that initiate the degradation of the glycoprotein matrix protecting the egg and allowing the sperm plasma membrane to fuse with the egg plasma membrane, as illustrated in Figure 24.23b. The fusion of these two membranes creates an opening through which the sperm nucleus is transferred into the ovum. The nuclear membranes of the egg and sperm break down and the two haploid genomes condense to form a diploid genome.
Answer:
C. primary cell wall → plasma membrane → cytoplasm → vacuole.
Explanation:
Every molecule or particle which enters into a cell, it must pass through several cellular structure at different level means it also depends on the type of molecule like size, shape, and nature (characteristics). On the surface of root cell, potassium ion pass through the primary cell wall which is most outer layer of plant cell, then it passes the second layer called plasma membrane, in the plasma membrane cytoplasm is present and when potassium ion reaches the cytoplasm then it will enter into the vacuole present in cytoplasm.
Answer:
Option A
True
Explanation:
Adenosine triphosphate (ATP) is the molecule in the cells that carry energy. They help to trap the energy that is obtained during respiration and the breaking down of food, in order to release it to the cells of the living organisms when the need arises.
Once the ATP levels deplete in the body, cellular fatigue begins to occur, as the cells do not have the required energy to perform their necessary functions.
This makes the correct option to be A: True. The depletion of the ATP levels in the body causes fatigue
<span>What is the approximate age of our solar system?
</span>b. 4.6 billion years
