Ques: Q: How many chromosomes are in each set? Read this paragraph and choose the correct option from the provided answers: Human cells normally have two sets of chromosomes, one set inherited from each parent. There are 23 chromosomes in each set, for a total of 46 chromosomes per cell. Each chromosome in one set is matched by a chromosome of the same type in the other set, so there are actually 23 pairs of chromosomes per cell. Each pair consists of chromosomes of the same size and shape that also contain the same genes. The chromosomes in a pair are known as homologous chromosomes . Choices: - 22 - 21 - 13 - 23 A:
Ans: 23

Ques: Q: What do the gonadotropins regulate? Read this paragraph and choose the correct option from the provided answers: Choices: - temperature - epigenesis - mitosis - gametogenesis A:
Ans: gametogenesis

Ques: Q: What specific part of the brain regulates the endocrine system? Read this paragraph and choose the correct option from the provided answers: The endocrine system consists of glands that secrete hormones into the bloodstream. It is regulated by a part of the brain called the hypothalamus, which also secretes hormones. The hypothalamus controls the pituitary gland, which is called the "master gland" of the endocrine system because its hormones regulate other endocrine glands. Other endocrine glands include the thyroid gland and pancreas. Choices: - parietal lobe - hippocampus - frontal lobe - hypothalamus A:
Ans: hypothalamus

Ques: Q: Before the atmosphere became oxygenated, the planet was subjected to what harmful energy source, meaning the first organisms would have flourished where they were more protected? Read this paragraph and choose the correct option from the provided answers: Before the atmosphere became oxygenated, the planet was subjected to strong radiation; thus, the first organisms would have flourished where they were more protected, such as in ocean depths or beneath the surface of Earth. At this time, too, strong volcanic activity was common on Earth, so it is likely that these first organismsthe first prokaryoteswere adapted to very high temperatures. These are not the typical temperate environments in which most life flourishes today; thus, we can conclude that the first organisms that appeared on Earth likely were able to withstand harsh conditions. Microbial mats may represent the earliest forms of life on Earth, and there is fossil evidence of their presence, starting about 3.5 billion years ago. A microbial mat is a large biofilm, a multi-layered sheet of prokaryotes (Figure 13.3a), including mostly bacteria, but also archaea. Microbial mats are a few centimeters thick, and they typically grow on moist surfaces. Their various types of prokaryotes carry out different metabolic pathways, and for this reason, they reflect various colors. Prokaryotes in a microbial mat are held together by a gummy-like substance that they secrete. The first microbial mats likely obtained their energy from hydrothermal vents. A hydrothermal vent is a fissure in Earth's surface that releases geothermally heated water. With the evolution of photosynthesis about 3 billion years ago, some prokaryotes in microbial mats came to use a more widely available energy sourcesunlightwhereas others were still dependent on chemicals from hydrothermal vents for food. Choices: - evaporation - conduction - convection - radiation A:
Ans:
radiation