bio exam 3

breathing is usually regulated by

CO2 and O2 concentration and pH-level sensors.

Which of the following statements correctly describes the alternation of generations in a plant life cycle?

Diploid sporophytes that produce spores by meiosis alternate with haploid gametophytes that produce gametes by mitosis

In a resting potential, an example of a cation that is more abundant as a solute in the cytosol of a neuron than it is in the interstitial fluid outside the neuron is ____.

K+

Which statement about resting potential is true?

The sodium-potassium pump contributes to the resting membrane potential.

How are hormones distributed to tissues, and what determines which cells they will affect?

They are carried to the body through the bloodstream, and each hormones affects target cells with receptors.

which of the following statements regarding circulatory systems is true?

a circulatory system is necessary in any animal whose body is too large or too complex for vital chemicals to reach all parts of the body by diffusion.

organisms with a circulating body fluid that is distinct from the fluid that directly surrounds the body's cells are likely to have ____.

a closed circulatory system

which of the following animals would most likely be able to exchange gases effectively when placed in a dry desert environment

a dolphin

which option correctly lists the direction carbon dioxide travels as it leaves the body of a human

alveoli, bronchioles, bronchi, trachea, larynx, pharynx

An increase from pH 7.1 to pH 7.5 around hemoglobin causes

an increase in the affinity of hemoglobin to bind to oxygen molecules

the majority of plant species today are

angiosperms

in angiosperms, pollen grains develop in the _____ and land on the _____.

anther; stigma

which of the following options correctly represents the most likely sequence of the evolution of plants, from earliest to most recent?

bryophytes, seedless vascular plants, gymnosperms, angiosperms

In a moss, most of the plants that we see are ____; in a fern, the most dominant stage is the ____.

byrophytes/gametophytes; sporophyte

a waste product of cellular respiration is

carbon dioxide

although birds and mammals descended from different ancestors, they both have a four-chambered heart. This is the result of

convergent evolution?

which of the following statements regarding ferns is true?

ferns have well-developed vascular tissue, roots, and stems

which of the following characteristics tends to limit bryophytes and seedless vascular plants to habitats that are relatively moist?

flagellated sperm

the simplest animals to display cephalization and centralization of the nervous system are

flatworms

heterotrophic eukaryotes that digest their food externally and absorb the small molecules are referred to as

fungi

the dominant stage of the moss life cycle is the

gametophyte

which part of the life cycle does a pollen grain represent?

gametophyte

which of the following organisms has a respiratory system that does not require assistance from a circulatory system for gas exchange?

grasshopper

ferns and mosses are similar because both

have flagellated sperm

A leaf with a higher density of stomata can take up more CO2 and release more water than a leaf with a lower density of stomata. The stomata found on fossil plants can be a reliable way to measure past carbon dioxide levels. Normally, fossil plants with a high density of stomata indicate ____ carbon dioxide levels and fossil plants with only a few stomata indicate ____ carbon dioxide levels.

high; low

threadlike fungal filaments are called

hyphae

one advantage of gas exchange in water is that

it is easy to keep the exchange surface wet

blood returning to a mammal's heart from the lungs first goes where?

left atrium

Which of the following features would you expect to see in the flowers of wind-pollinated grasses?

mass quantities of pollen

the intimate, mutually beneficial association formed between a fungus and the root of a plant is called a

mycorrhiza

the reason animals need a continuous supply of oxygen is to

obtain energy from their food

The _____ is the protective chamber that houses the ovule and later matures to become the fruit.

ovary

in plants, the vascular tissue that consist of living cells that distribute sugars throughout the plant is called

phloem

which of the following plants has a dominant sporophyte generation and a seed, but no fruit?

pine trees

two characteristics shared by gymnosperms and angiosperms that are absent from earlier plant groups and represent key adaptations to life on dry land are

pollen and seeds

which of the following represents the male gametophyte of a confier?

pollen grain

Which of the following characteristics tends to limit bryophytes and seedless vascular plants to habitats that are relatively moist?

presence of flagellated sperm

Once an action potential is triggered, there is a

reversal of the membrane polarity, with the interior of the cell becoming positively charged.

When you hold your breath, which of the following blood gas changes first leads to the urge to breathe?

rising CO2

the endocrine system when compared to the nervous system has a

slower response with a longer-lasting signal

which of the following animals has a three-chambered heart?

snake (amphibians and reptiles)

the concentrations of ions are very different inside and outside a nerve cell due to

sodium-potassium pumps

which of the following structures is an essential part of most fungal reproductive systems

spores

the structural integrity of bacteria is to peptidoglycan as the structural integrity of plant spores is to

sporopollenin

CO2 enters a leaf and O2 escapes from a leaf via

stomata

the tracheal system of an insect is most like which of the following?

the air duct system in a building

Gills are unsuitable for animals living on land because

the large external surface area of the gills would allow for dehydration of the animals

air rushes into the lungs of humans during inhalation because

the rib muscles and diaphragm contract, increasing the lung volume

which of the following respiratory systems does not transport oxygen with blood?

the skin of an earthworm

how are hormones distributed to tissues, and what determines which cells they will affect?

they are carried by the bloodstream, and each hormone affects target cells that have receptors for it

Which of the following the correct sequence of blood flow in birds and mammals?

vena cava --> right atrium --> right ventricle --> pulmonary artery

in plants, the vascular tissue made of dead cells that transport water and minerals from the roots is called

xylem