What does it mean for a cell membrane to be selectively permeable?

A. It allows some substances to pass through but blocks the passage of others.

B. It allows only water molecules to pass through.

The seeds in a pine tree are borne in the: stigma ovulate cone microsporangiate cone microsporangium

A dichotomous key is a way of sorting organisms based on A : whether they are unicellular or multicellular B : the types of cells they are made out of C : a series of yes/no questions D : whether organisms are autotrophs or heterotrophs

Compare the properties of a raw egg to those of a boiled egg.

Why are single-stranded binding proteins necessary for DNA replication? a. They provide the energy necessary to separate the two strands of DNA. b. They direct the primase where to lay down the primer. c. None of the answer options is correct. d.

Scientists communicate the details of experiments so that

5. Which is the first step of the scientific method?

Identify the four postulates of natural selection. Select all that apply. 1. Individuals in a population all possess the same traits. 2. All individuals in a population have equal reproductive success. 3. Some trait differences are heritable. 4.

Competition is central to the theory of natural selection. why does competition occur?

Name three geological processes that have shaped the earth

In Mendel's Pea Plant Experiment, the color of the seed is an example of A. a trait B. recessive C. an allele