The graph illustrates the activity level of three common digestive enzymes, across a range of pH values. Which enzyme is likely to be the most active in the acidic environment of the stomach?
A) pepsin
B) trypsin
C) amylase
D) pepsin and trypsin
In animals, stem cells are specific types of cells which are able to differentiate into many different types of cells due to the expression of certain genes. What is the name of the type of cells in higher plants which have the same type of function as stem cells?
A) vascular cells
B) sporophyte cells
C) gametophyte cells
D) meristematic cells
Following the nuclear reactor accidents in Japan in April, 2011, some people were exposed to high levels of radiation. Children born to these people in the future could have mutations if these mutations occurred in the parents’
A) sex cells.
B) skin cells.
C) brain cells.
D) internal organs.
Suppose a mother carries two recessive genes for freckles (rr) and a father carries one recessive gene for freckles and one dominant gene for clear facial skin (Rr). What is the likelihood that their first child will have freckles?
A) 1/2
B) 1/4
C) 3/4
D) 4/4
The cell membrane is selectively permeable. O2 diffuses across the phospholipid bilayer. K+ must cross the cell membrane using a membrane protein. Which property of the cell membrane prevents the diffusion of K+?
A) The membrane proteins are attracted to the charged ions.
B) Only very small particles are able to diffuse across the cell membrane.
C) The lipid tails are hydrophobic, repelling charged ions such as K+.
D) The phosphate heads are hydrophobic and prevent the passage of polar substances.
There's about 34ish question's and I just want to make sure I have the right answer's. Thank you! :)
So what are your answers to each question then?
Based on the given information, the correct answers to the questions are as follows:
1) The enzyme that is likely to be most active in the acidic environment of the stomach is A) pepsin.
2) In higher plants, the type of cells that have the same function as stem cells are D) meristematic cells.
3) Children born to people who were exposed to high levels of radiation could have mutations if these mutations occurred in the parents' A) sex cells.
4) The likelihood that their first child will have freckles is B) 1/4.
5) The property of the cell membrane that prevents the diffusion of K+ is C) The lipid tails are hydrophobic, repelling charged ions such as K+.
Please note that it's important to refer to the specific information provided in the question to ensure the accuracy of the answers.
In order to determine the correct answers to the questions, let's analyze each question and explain how to arrive at the correct answer:
1) For the first question, we need to identify which enzyme is most active in an acidic environment. The options are: A) pepsin, B) trypsin, C) amylase, D) pepsin and trypsin. The enzyme that is most active in an acidic environment is pepsin, which is found in the stomach. Therefore, the correct answer is A) pepsin.
2) The second question asks about the type of cells in higher plants that have a similar function as stem cells. The options are: A) vascular cells, B) sporophyte cells, C) gametophyte cells, D) meristematic cells. The type of cells in higher plants that have a similar function as stem cells are meristematic cells. These cells have the ability to differentiate into various cell types and are responsible for growth and development in plants. Therefore, the correct answer is D) meristematic cells.
3) The third question asks about the type of cells in the parents that could result in mutations in their children due to radiation exposure. The options are: A) sex cells, B) skin cells, C) brain cells, D) internal organs. Mutations caused by radiation exposure in parents would be passed on to their children through their sex cells (sperm and eggs). Therefore, the correct answer is A) sex cells.
4) The fourth question asks about the likelihood of their first child having freckles based on the parents' genetic makeup. The mother has two recessive genes for freckles (rr) and the father has one recessive gene for freckles and one dominant gene for clear facial skin (Rr). The child will inherit one gene from each parent, resulting in three possible combinations: Rr, Rr, and rr. Out of these combinations, only the rr combination results in freckles. Therefore, the likelihood of their first child having freckles is 1 out of 4, making the correct answer B) 1/4.
5) The last question relates to the property of the cell membrane that prevents the diffusion of K+. The options are: A) the attraction of membrane proteins to charged ions, B) the limited diffusion of very small particles across the membrane, C) the hydrophobic nature of lipid tails repelling charged ions, D) the hydrophobic phosphate heads preventing the passage of polar substances. K+ is a charged ion, and it cannot diffuse directly through the lipid bilayer. Instead, it requires membrane proteins to facilitate its transport across the membrane. Therefore, the correct answer is C) the hydrophobic nature of lipid tails repelling charged ions.
Please note that while these explanations provide the correct answers based on the information provided, it is always helpful to double-check them using additional resources or consulting with a subject matter expert to ensure accuracy.
1.A
2.C
3.A
4.A
5.D