Which of the following species reproduces by internal fertilization?
a) cats
(b) Toads
(c) The fish
(d) alternative b and c
Answer:
(a) Los gatos
Explanation:
Only cats are capable of internal fertilization from the given choices above.
Internal fertilization is the fusion of gametes within an organism. This process occurs during sexual reproduction within the female.
- Toads and fishes exhibit external fertilization.
- External fertilization occurs where the male sperm externally fertilizes the eggs of the female.
- This usually takes place in a moist or wet place especially water bodies. The liquid medium will transport the sperm to the egg.
In cats, the female specie takes in reproductive cells from the male during coitus and it fertilizes the her eggs to produce a zygote.
Answer:
Dissimilar organisms might have evolved from a distant, common ancestor.
Explanation:
First of all we should know species. Species is considered as a basic unit of taxonomic classification of an organism.
Initially, the scientists are agreed on this phenomenon that all distinct species are evolved gradually from common ancestor. Today, the species which are different from each other just like hummingbirds, humans and whales are from the same ancestor but with the time passage genetic mutation occurs and at the end dissimilar organisms we can see in our environment/surroundings.
Answer:
1. 80 chromosomes are found in each of the daughter cells. 2. Two daughter cells are produced. 3. The daughter cells are identical to each other.
Explanation:
Mitosis is simply a process of cell division whereby two daughter cells that are genetically identical are produced from a single parent cell. A cell having 80 chromosomes would undergo Mitosis through these various stages:
Interphase: This can be referred to as the rest phase between cell division when mature enough for reproduction. This is a preparatory stage where DNA is duplicated and ready for the division of chromosomes
Prophase: This stage marks the beginning mitosis of the cell with 80 chromosomes. The chromatin threads start a coiling process in which the chromosomes become condensed to enable easy distribution to daughter cells without tangling.
Prometaphase: This phase commences toward the end of the prophase, where the nuclear envelop breaks down. The chromosomes move toward to the center of the cell.
Metaphase: At this stage, the duplicated chromosomes line up on the mid plane or equator of the cell. During this stage, each chromatid is condensed completely and appears thick and distinct.
Anaphase: At this stage, the chromosomes move toward the poles as each replicated copies of the DNA of the cell ends up on either side of the cell. What we would have here at this stage is an entirely two new sister chromatid having 80 chromosomes. Cytokinesis begins towards the end of this stage as the parent cell cytoplasm divides which also continues at telophase.
Telophase: This is the final phase of Mitosis where two separate nuclei are formed and Cytokinesis takes place to complete the division of the cell to form two daughter cells having the same number of chromosomes. These cells are genetically identical to the original parent cell.
Answer:
There is no actual way that the mantle could be...'exposed' or 'seen'. But scientists have managed to find multiple ways to analyze the mantle and it's actual existence by using multiple devices. The mantle is basically a 2,900 kilometers (1,802 miles) thick blocks of rocks and minerals underneath the crust(or the surface of the earth) , and makes up a whopping 84% of Earth's total volume.
