Ribosome
nucleus are the answers
Through the process of meiosis. During meiosis, crossing-over occurs and increases genetic diversity. The haploid cells formed from meiosis (sperm or egg) have half the chromosomes so when the two meet they combine and share different chromosomes.
Answer:
B. a decrease in the number of pathogens in the body
Explanation:
White blood cell includes immune cell like monocytes, macrophages, neutrophils, basophils, eosinophils, etc. These cells are responsible for fighting with the pathogens or foreign molecules and eliminate them from the body.
So when any pathogens get enter in the body these cell kills those pathogen and protect us from them. Therefore the decrease in the number of pathogens in the body is a direct indication that the white blood cells in the body are working. So the right answer is B.
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.