False. I don't know how to explain it but they don't classify as living.
A. Heat will not flow because there is no temperature difference between the substances.
Answer: The Heart
Explanation:
The blood circulatory system (cardiovascular system) delivers nutrients and oxygen to all cells in the body. It consists of the heart and the blood vessels running through the entire body. The arteries carry blood away from the heart; the veins carry it back to the heart. The system of blood vessels resembles a tree: The “trunk” – the main artery (aorta) – branches into large arteries, which lead to smaller and smaller vessels. The smallest arteries end in a network of tiny vessels known as the capillary network.
There are two types of blood circulatory system in the human body, which are connected: The systemic circulation provides organs, tissues and cells with blood so that they get oxygen and other vital substances. The pulmonary circulation is where the fresh oxygen we breathe in enters the blood. At the same time, carbon dioxide is released from the blood.
Blood circulation starts when the heart relaxes between two heartbeats: The blood flows from both atria (the upper two chambers of the heart) into the ventricles (the lower two chambers), which then expand. The following phase is called the ejection period, which is when both ventricles pump the blood into the large arteries.
In the systemic circulation, the left ventricle pumps oxygen-rich blood into the main artery (aorta). The blood travels from the main artery to larger and smaller arteries and into the capillary network. There the blood drops off oxygen, nutrients and other important substances and picks up carbon dioxide and waste products. The blood, which is now low in oxygen, is collected in veins and travels to the right atrium and into the right ventricle.
This is where pulmonary circulation begins: The right ventricle pumps low-oxygen blood into the pulmonary artery, which branches off into smaller and smaller arteries and capillaries. The capillaries form a fine network around the pulmonary vesicles (grape-like air sacs at the end of the airways). This is where carbon dioxide is released from the blood into the air inside the pulmonary vesicles, and fresh oxygen enters the bloodstream. When we breathe out, carbon dioxide leaves our body. Oxygen-rich blood travels through the pulmonary veins and the left atrium into the left ventricle. The next heartbeat starts a new cycle of systemic circulation. Below is an attachment of a diagram that explains the connection between pulmonary and systemic circulation from google.
Answer:
C. Point B
Explanation:
The exposed curve represents a logistic growth model. Population growth depends on density. Natality and mortality depend on the population size, meaning that there is no independence between population growth and population density.
When a population grows in a limited space, density rises gradually and eventually affects the multiplication rate. The population per capita growth rate decreases as population size increases. The population reaches a maximum point delimited by available resources, such as food or space. This point is known as the carrying capacity, K.
K is a constant that equals population size at the equilibrium point, in which the natality and the mortality rate get qual to each other.
Referring to population size as N, when
- N<K, the population can still grow.
- N approximates to K, the population´s growth speed decreases.
- N=K the population reaches equilibrium,
- N>K, the population must decrease in size because there are not enough resources to maintain that size.
The sigmoid curve represents the logistic growth model.
- Point A: During this period, the population size is relatively stable. Little growth is expressed.
- Point B: At the beginning of this period, population growth increases softly. The more individuals are in the population, the more that reaches sexual maturity and get to reproduce, leaving fertile offspring. This fertile offspring also get to reproduce and leave more fertile individuals. At the end of the period, the curve shows a sharp slope, reflecting the significant increase in the population reproductive rate.
- Point C: At the beginning of this period, the population keeps on growing exponentially. But at the end of the period, the curve tends to stabilize, meaning that the population stops growing in size so fast. The population slow and gradually reaches the equilibrium point, K.
- Point D: The population got to stabilize.
1. the water levels are droping in areas.
2. their are more frogs being hunted now.
3. Their food supply is going down