Answer the following question given this paragraph: Birds are endothermic tetrapod vertebrates. They are bipedal, which means they walk on two legs. Birds also lay amniotic eggs with hard, calcium carbonate shells. Although birds are the most recent class of vertebrates to evolve, they are now the most numerous vertebrates on Earth. Why have birds been so successful? What traits allowed them to increase and diversify so rapidly? Birds can vary considerably in size, as you can see from the world's smallest and largest birds, pictured in Figure below . The tiny bee hummingbird is just 5 centimeters (2 inches) long, whereas the ostrich towers over people at a height of 2.7 meters (9 feet). All modern birds have wings, feathers, and beaks. They have a number of other unique traits as well, most of which are adaptations for flight. Flight is used by birds as a means of locomotion in order to find food and mates and to avoid predators. Although not all modern birds can fly, they all evolved from ancestors that could. Q: How do bipedal creatures walk? Choices: - on twelve legs - on six legs - on four legs - on two legs A:
on two legs
Answer the following question given this paragraph: All the atoms of a given element have the same number of protons and electrons. The number of neutrons, however, may vary for atoms of the same element. For example, almost 99 percent of carbon atoms have six neutrons, but the rest have either seven or eight neutrons. Atoms of an element that differ in their numbers of neutrons are called isotopes. The nuclei of these isotopes of carbon are shown in the Figure below . The isotope called carbon-14 is used to find the ages of fossils. You can learn how at this URL: http://science. howstuffworks. com/environmental/earth/geology/carbon-14. htm . Q: How many neutrons do 99% of carbon atoms have? Choices: - sixteen - five - eight - six A:
six
Q: Answer the following question given this paragraph: Flickr:Image Editor. Planets in the solar system make elliptical orbits around the Sun . CC BY 2.0. Q: What kind of movement do planets in the solar system make around the sun? Choices: - optical orbits - round orbits - spinning orbits - elliptical orbits A:
A: elliptical orbits
Question: Answer the following question given this paragraph: Like the stem, the leaf contains vascular bundles composed of xylem and phloem (Figure 30.27). The xylem consists of tracheids and vessels, which transport water and minerals to the leaves. The phloem transports the photosynthetic products from the leaf to the other parts of the plant. A single vascular bundle, no matter how large or small, always contains both xylem and phloem tissues. Q: Like the stem, what basic plant structure contains vascular bundles composed of xylem and phloem? Choices: - root - flower - bark - leaf A:
Answer: leaf
*Question*
Answer the following question given this paragraph: What is a cell? Gradient Physical difference between two regions of space, in such a way that the molecules tend to move in response to the gradients. Diffusion Movement of the molecules in a fluid, from the regions of high concentration to those of low concentration. Passive transport Movement of substances in a membrane that doesn't need to use energy. Simple diffusion Diffusion of water, gases or molecules across the membrane. Facilitated diffusion Diffusion of molecules across the membranes with the participation of proteins. Osmosis Diffusion of the water across a membrane with differential permeability. Transport that needs energy Movement of substances across a membrane generally in opposition to a gradient of concentration with the requirement of energy. Active transport Movement of small molecules using energy (ATP). Endocytosis Movement of big particles towards the interior of the cell using energy. The cells enclose particles or liquids. Pinocytosis (Literally cell drinking) Form in which the cell introduces liquids. Phagocytosis Way of eating of the cells. It feeds in this case of big particles or entire microorganisms. Pseudopods False feet (the amoeba). Exocitosis Movement of materials out of the cell with the use of energy. It throws waste material. Isotonic The cytoplasm fluid of the interior of the cells is the same that the outer. Hypertonic solution. Q: Pseudopods are false what? Choices: - eyes - teeth - fingers - feet A:
**Answer**
feet
(Q).
Answer the following question given this paragraph: 17.8 Gonadal and Placental Hormones The male and female reproductive system is regulated by follicle-stimulating hormone (FSH) and luteinizing hormone (LH) produced by the anterior lobe of the pituitary gland in response to gonadotropin-releasing hormone (GnRH) from the hypothalamus. In males, FSH stimulates sperm maturation, which is inhibited by the hormone inhibin. The steroid hormone testosterone, a type of androgen, is released in response to LH and is responsible for the maturation and maintenance of the male reproductive system, as well as the development of male secondary sex characteristics. In females, FSH promotes egg maturation and LH signals the secretion of the female sex hormones, the estrogens and progesterone. Both of these hormones are important in the development and maintenance of the female reproductive system, as well as maintaining pregnancy. The placenta develops during early pregnancy, and secretes several hormones important for maintaining the pregnancy. Q: The male and female reproductive system is regulated by follicle-stimulating hormone (fsh) and luteinizing hormone (lh) produced by what gland? Choices: - thyroid - testes - adrenal - pituitary A:
(A).
pituitary