Honors Biology Semester 2 Final Exam Study Guide Flashcards

Comprehensive practice questions and answers covering Heredity, Evolution, and Human Body systems for the Honors Biology Semester 2 Final Exam.

If a diploid cell in an organism has $4$ chromosomes, how many chromosomes are in its haploid cell?

$$2$$

How do sperm and egg cells differ genetically in terms of sex chromosomes?

Sperm are $XY$ and Eggs are $XX$.

Why do Calico cats show patches of both black and orange fur?

It is a case of codominance where females with the black allele ($B$) and the orange allele ($b$) express both colors.

What are the expected offspring phenotypes from a cross between an O blood type mother ($ii$) and an AB blood type father ($I^AI^B$)?

$50\%$ Type A ($I^Ai$) and $50\%$ Type B ($I^Bi$).

In mice fur color (incomplete dominance), what are the expected offspring percentages from a cross between two gray mice?

$25\%$ Black, $50\%$ Gray, and $25\%$ White.

If long hair ($H$) is dominant to short hair ($h$) and a litter has $5$ long-haired and $4$ short-haired puppies, what are the likely genotypes of the parents?

$Hh$ and $hh$

What inheritance pattern is indicated by a pedigree that only affects males?

Sex-linked recessive

What chromosomal abnormality is identified by the presence of three chromosomes at position 13?

Trisomy 13

How does antibiotic resistance demonstrate natural selection?

Bacteria that are resistant to antibiotics survive and pass that resistance on to their offspring.

According to the study guide, what is a specific concern regarding antibiotic sales to farms?

It may increase antibiotic resistance in bacteria found in livestock, and sales have increased every year since 2003.

What is the evolutionary significance of organisms having homologous structures, such as sharing the same bone arrangements?

It suggests they share a common ancestor.

How is embryology used as evidence for evolution?

Shared characteristics in early development stages support the idea that organisms have the same basic DNA instructions.

What are structures called when they have the same function but different evolutionary origins, such as different wing types?

Analogous structures (Convergent evolution)

What are vestigial structures?

Traits that ancestors had but the current organism no longer needs or uses, such as the pelvis and femur in a snake.

What type of evidence for evolution is considered the most decisive?

DNA evidence (Comparative biochemistry)

What is the difference between positive and negative feedback loops?

Positive feedback increases a stimulus until a response is reached; negative feedback reverses a stimulus to balance a system.

What are the roles of glucagon and insulin in blood glucose homeostasis?

Glucagon increases blood glucose, while insulin decreases blood glucose.

What occurs during pulmonary circulation?

Blood travels from the heart to the lungs and back to the heart.

What is the correct path of food through the digestive tract?

Mouth, esophagus, stomach, small intestine, large intestine, and anus.

What are the digestive roles of the liver and the gallbladder?

The liver creates bile to digest fats, and the gallbladder stores that bile.

Where does mechanical digestion occur in the human body?

In the mouth and the stomach.

How do the kidneys maintain homeostasis when a person is dehydrated?

They retain/hold on to water and decrease urine production.

Why is it beneficial for alveoli to be covered in capillaries?

To increase surface area so that oxygen and carbon dioxide can diffuse more efficiently.

How does a nervous signal travel from one neuron to another?

Electrical impulses trigger the release of neurotransmitters from the axon, which cross the synapse and are detected by the dendrites of the next cell.

What are the functions of leukocytes and platelets in the immune system?

Leukocytes (and phagocytes) destroy pathogens, while platelets aid in blood clotting.

What are the three primary reasons cells undergo mitosis?

Growth, Repair, and Renewal.

Why do both pulmonary and systemic circulation need to occur?

The blood needs to pick up oxygen and release carbon dioxide before it can return to the body tissue.

What is happening in systemic circulation?

Blood is pumped throughout the body to deliver oxygen and nutrients to tissues and organs.

What is the function of the pancreas in digestion?

The pancreas secretes digestive enzymes that help break down food in the small intestine.

What is chemical digestion and where does it occur?

Chemical digestion is the chemical breakdown of food; it occurs in the mouth, stomach, and intest

What is the role of the circulatory system?

Pumps blood throughout the body to control temperature, pH, water balance, and transport nutrients, oxygen, and carbon dioxide.

why does the oxygen from the inhaled air move into the blood?

Diffusion - gases move from high concentration to low concentration

 What is a neurotransmitter and what is its role?

Chemical messengers that cross the synapse between neurons to start an action potential. Released from the axon and picked up by the dendrites.