Answer:
I'm not sure what the answers are but
Polar bears begin to eat goose eggs as a way to survive when seals, their usual prey, are not available.
Mountain goats restrict their range to higher altitudes because of warmer low-altitude temperatures.
Snowshoe hares change their fur from white to brown to match their warm summer habitats.
Early humans learn to make tools like flint arrows and knives to help them hunt more efficiently.
if these are your options then the answer is
C) Snowshoe hares change their fur from white to brown to match their warm summer habitats.
1. In the heart, an action potential originates in the (E) sinoatrial node.
The cardiac action potential is a term referring to the change in the membrane potential of heart cells causing the heart to contract. Cardiac action potentials are created by a group of specialized cells capable of generating automatic action potentials and are located in the right atrium of the heart. These cells are called sinoatrial node and sometimes are referred to as the natural pacemaker of the heart. This characterization originates from the fact that sinoatrial node continuously provides action potential and sets the rhythm of the heart function.
2. The sequence of travel by an action potential through the heart is (A) sinoatrial node, atrioventricular node, atrioventricular bundle, bundle branches, Purkinje fibers.
As explained above, the cardiac action potential originates from the sinoatrial node. This action potential then travels through the atrioventricular node, which belongs to the electrical conduction system of the heart and is located between the atria and the ventricles. It is responsible for the electrical connection between the right atrium and the right ventricle. The action potential then travels to the atrioventricular bundle (or bundle of His), another part of the electrical conduction system of the heart. The atrioventricular bundle transmits the electrical impulses from the atrioventricular node to the bundle branches. The bundle branches then send the signal to the Purkinje fibers which send the electrical impulses to the ventricles, causing them to contract.
3. The correct answer is A.
The generation of an action potential in the sinoatrial node causes the contraction of the atria. When the action potential passes from the sinoatrial node to the atrioventricular node, it slows down. This causes the transport of the electrical impulse from the atria to the ventricles to slow down. This delay enables the blood (from the contraction of the atria) to fill the ventricles before their contraction.
4. This statement is true.
The interventricular septum is a structure which divides the two ventricles of the heart and it is composed of two branches, the left bundle and the right bundle branch. When the action potential reaches the interventricular septum, it then travels to the apex of the heart from where it travels upwards along the walls of the ventricles and the ventricular contraction begins.
5. This statement is true.
The bundle branches gradually become Purkinje fibers located in the interior of the ventricular walls. Purkinje fibers are specialized cells and are responsible for conducting cardiac action potentials from the bundle branches to the ventricular walls. This signal transduction causes the muscle of the ventricular walls to contract.
The natural selection is the survival of the fittest, which means that o<span>nly the best adapted individuals survive and reproduce, contributing the most to the next generation</span>
According to natural selection, birds such as cardinals , eagles, and ducks have differently shaped feet due to <span>adaptation to different environments and feeding habits.
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Answer:
only females
Explanation:
In humans, sex chromosomes in males and females are different. The sex chromosomes found in humans are X and Y chromosomes. X-linked trait is a trait which is inherited on the X- chromosome. According to the question, the trait is passed on a X-linked dominant condition, which means the condition is inherited on the abnormal dominant X-chromosome that will express itself even when in an heterozygous state with a normal X-chromosome.
Hence, a father affected by the condition will have a genotype; XY while a mother that does not have the condition will have a genotype: xx (two normal x chromosomes). Since the Father can only pass his X chromosome to his daughters and never his sons, all his daughters will inherit the condition (see the punnet square in attached image).
N.B: None of the sons will inherit the condition since the mother will pass normal X-chromosomes (x) to her sons.
Answer:
Giraffe Habitat
Explanation:
Giraffes can inhabit savannas, grasslands or open woodlands. Giraffes prefer areas enriched with acacia growth (a genus of shrubs and trees). Most giraffes live either in East Africa or in Angola and Zambia in southwestern Africa.
