The channels in cell membranes that help substances to move in and out of cells during active transport are made of
A. protein.
B. chlorophyll.
C. cytoplasm
D. carbohydrates.

The images show the wings of a bat and a bee. from this evidence, what can you conclude about the evolutionary relationship between these organisms? a. the wing structures of the bat and the bee are different, indicating they didn’t inherit wings from a common ancestor. b. the wing structures of the bat and the bee are different, indicating they inherited wings from a common ancestor. c. the functions of bat wings and bee wings are the same, indicating they obtained wings from a common ancestor. d. the functions of bat wings and bee wings are different, indicating they didn’t obtain wings from a common ancestor.

Which set of characteristics best describes sedimentary rock? a) largest type of rock, made of organic matter, hardest type of rock b) often contains layers, forms near sources of water, contains fossils c) least abundant type of rock, made of other rocks, made mostly of minerals d) most abundant type in earth's crust, made of magma/lava, contains no fossils

Several bird species feed in a certain species of tree. each bird species feeds in a different part of the tree. which statement is true of these bird species? a. they have adapted to different niches due to competition b. they have a carnivorous relationship with the tree species. c. they have adapted to different niches due to predation d. they have a symbiotic relationship with the tree species.