Biology Unit 4

What cells in nervous tissue carry electrical signals?

neurons

Most nerve cells are separated by space (called a gap, or synapse). How does a nerve impulse travel across this space?

one neuron secretes a chemical (neurotransmitter) that stimulates the next neuron

Which of the following is a function of the helper T cells?

secrete cytokines

Which of the following is not an endocrine organ?

spleen

The hormone that primarily maintains the composition of body fluids is

antidiuretic hormone (ADH)

A molecule that stimulates an immune system reaction by B cells and T cells is termed a(n)

antigen

Presented with a female patient who often fails to ovulate, leading to infertility, what hormone would you test to try to understand the cause of this problem?

follicle-stimulating hormone (FSH)

A layer of phospholipids is impervious to ions. How, then, do ions cross the phospholipid membrane of a neuron to transmit a nerve impulse?

They pass through the proteins embedded in the plasma membrane.

Some adult weight lifters dope with human growth hormone. What effect would this have on their bodies?

They would gain muscle.

A human embryo may have the chromosomes XX or XY. Which of these is a female?

XX

The main neurotransmitter in the sensory-somatic nervous system is _____________.

acetylcholine

What is able to pass across the placenta between the embryo/fetus during pregnancy?

all of these nutrients fetal waste products oxygen carbon dioxide carbon monoxide nicotine alcohol illegal street drugs small viruses

An exaggerated attack on a harmless antigen by an overly sensitive immune system is termed a(n)

allergy

Follicle-stimulating hormone (FSH) and luteinizing hormone (LH) are produced by the

anterior pituitary gland

The hormone prolactin is produced by the _____________ and targets the _____________.

anterior pituitary; mammary glands

When a nerve impulse travels from one neuron to another it follows this path:

axon, synapse, dendrite

Bacteria reproduce by _____ .

binary fission

Which stage in embryonic development is the embryo a hollow ball?

blastula

The placenta is part of the __________ body.

both the mother's and the fetus's

As the fertilized egg continues to develop in humans, a neural tube is formed. This neural tube will continue to develop and become the _____ .

brain and spinal column

The ______________ is the most ancient part of the brain. It coordinates motor control signals sent from the brain to the body. It controls several important functions of the body including alertness, arousal, breathing, blood pressure, digestion, heart rate, swallowing, walking, and sensory and motor information integration.

brainstem

Corals and hydras can reproduce by producing an outgrowth which becomes a new individual. This form of reproduction is known as _____ .

budding

Which part of the brain controls balance and aids in coordinating movement and learning new motor tasks?

cerebellum

Non-mammals, such as birds and reptiles, have a common body opening, called a _____ for the digestive, excretory and reproductive systems

cloaca

In a process called _____, an army of plasma cells and memory cells are produced from properly stimulated B cells.

clonal selection

When activated, __________ trigger(s) a chain reaction that punctures bacterial cell membranes.

complement proteins

Which part of a neuron receives the nerve impulse from another neuron?

dendrite

Which germ layer develops into the central nervous system and the epidermis?

ectoderm

A phagocyte is a cell that

engulfs other cells and debris

White blood cells are produced

from bone marrow stem cells

What is the first stage in human development in which there are three germ layers?

gastrula

The endocrine system consists of 2 main components: ____________ which have cells that produce and secrete _____________.

glands; hormones

The "master cells" of the immune system that initiate and coordinate the adaptive immune response are

helper T cells

When we compare the testes with the ovary, the penis with the clitoris, and the scrotum with the labia, we say that each pair is _____ .

homologous

All of the glands of the vertebrate endocrine system are regulated by the

hypothalamus and pituitary gland

The phospholipid membrane that is the cell membrane of the neuron is slightly electrically negative. One side is more negative than the other when the neuron is at rest, not transmitting a nerve impulse. Which side is more negative at rest?

inner surface

B cells and T cells are

lymphocytes

A person who is an organ transplant recipient must take immune suppressant drugs for the rest of his/her life because the donated organ will have a different ____.

major histocompatability complex

A cell that does not circulate in blood, but instead settles in tissues near the skin and in the digestive tract, producing and releasing histamine when tissue is damaged is a(n)

mast cell

Which cellular organelle is most obviously present and important in the sperm (other than the nucleus)?

mitochondria

A node of Ranvier is a break in the ______________

myelin sheath

What structure of the neuron both increases the speed of a nerve impulse and allows the neuron to function with less energy cost?

nodes of Ranvier

When someone has been knocked unconscious or falls and hits his head and then "sees stars," an injury to what part of his brain accounted for "seeing stars"?

occipital

One hormone functions both in causing uterine contractions during labor and in the production of milk. What is that hormone?

oxytocin

The endocrine gland that controls homeostasis in terms of blood glucose levels is the _______________

pancreas

Which can be a target of autoimmune disease but is not considered to be a major part of the immune system itself?

pancreas

Once a stressful situation is over and we calm down and can once again do things like digest our food it is because the ______________ nervous system is operating.

parasympathetic

Which of these forms of reproduction requires an egg?

parthenogenesis

Birds manage to have internal fertilization without a/an ___________.

penis

The endocrine gland that produces melatonin is the

pineal gland

Special cells produced by the immune system that are progeny of properly stimulated B cells and are antibody-producing factories are

plasma cells

Which of the following would be an indication that the parasympathetic nervous system is in control?

pupils constrict

The ____________ controls motor reflexes. These reflexes are quick, unconscious movements-like automatically removing a hand from a hot object.

spinal cord

Your text book speaks of epinephrine and adrenaline and norepinephrine being the neurotransmitters associated with the ______________ nervous system

sympathetic

What happens during parturition?

A baby is born

Physical and chemical barriers that form the first line of innate defense include

All of the answer choices are correct the acidity of the stomach tear fluid from the eye an unpunctured skin mucus and cilia of the respiratory tract

Which of these hormones are produced by human males?

All of these

____ are foreign molecules that stimulate the production of ____.

Antigens, antibodies

A human embryo develops into a male due to a hormone secreted by _________.

the embryo/fetus

Which of these statements is true?

Both eggs and sperm are produced by meiosis

An immunodeficiency means that ____.

the immune system lacks one or more essential components

Why is the presence of human chorionic gonadotropin a reliable test for pregnancy?

It is produced by the blastocyst

If a child is born on December 25 what is the most likely date of its conception?

March 25

Which of these statements about menopause and post-menopause is FALSE?

None are false; they are all true

Which of these methods of reproduction is an example of sexual reproduction?

None of these is an example of sexual reproduction

A preparation that "teaches" the immune system to recognize a disease-causing agent without actually causing disease is termed a(n)

vaccination

Which of these means of reproduction uses a placenta?

viviparity

Human sperm are motile only in an alkaline environment. The vagina of a woman in her childbearing years is usually acidic. How are sperm able to function in such an environment?

Semen contains an alkali to reverse the vaginal acidity

As the wave of electrical polar reversal and correction travels down the neuron what keeps the nerve impulse traveling in the right direction and keeps it from traveling backward?

The wave of correction that follows the nerve impulse actually "over-corrects" as some ion gates close and others are opened

In human males the Sertoli cells release the chemical inhibin when the sperm are too numerous and does not release it when more sperm need to be made? How do human females regulate the production of eggs within their lives?

They don't; they are born with enough