Question

which structure, found in both plant and animal cells, is most responsible for allowing the passage of some molecules into the cell while blocking the passage of others?
a cell wall
b endoplasmic reticulum
c nucleus
d cell membrane
question 27 (1 point)
payten knows that the only way that she will ever have a chance of becoming the flag football team captain is if she is extremely strong. for this reason, she does many squats, lunges, and sprints as part of her training. which two organelles would be in great abundance in her leg muscles?
a vacuoles and vesicles
b mitochondria and lysosomes
c nucleus and cytoplasm
d rough er and ribosomes

Explanation:

Question 1 (Cell Structure Permeability)

• Option a: Cell wall is only in plant cells, not animal cells. Eliminate.
• Option b: Endoplasmic reticulum is for protein/lipid synthesis, not selective transport. Eliminate.
• Option c: Nucleus controls cell activities, not transport. Eliminate.
• Option d: Cell membrane (plasma membrane) is in both plant/animal cells and is selectively permeable, controlling molecule passage. Correct.

• Option a: Vacuoles/vesicles store materials, not for muscle energy/function. Eliminate.
• Option b: Mitochondria produce ATP (energy) for muscle activity; lysosomes break down waste/damaged parts. Muscle cells need energy (mitochondria) and waste management (lysosomes). Plausible. Wait, correction: Lysosomes are not abundant in muscle cells for energy. Wait, muscle cells need mitochondria (energy) and maybe rough ER/ribosomes? No, re - evaluate:

Wait, muscle cells need energy (mitochondria) and for muscle contraction, but the options:
Wait, the correct organelles for muscle cells (high energy demand) are mitochondria (produce ATP) and also, muscle cells have sarcoplasmic reticulum (a type of ER), but among the options:
Wait, the options:

• Option b: Mitochondria (energy) and lysosomes (breakdown). But lysosomes are not the main ones. Wait, maybe a mistake. Wait, the other options:
• Option c: Nucleus and cytoplasm are not organelles (cytoplasm is a region, nucleus is an organelle but not abundant for muscle function). Eliminate.
• Option d: Rough ER and ribosomes make proteins. Muscle cells (like muscle fibers) have myofibrils, and muscle cells do have rough ER (sarcoplasmic reticulum is a type, but rough ER with ribosomes makes proteins for muscle structure? Wait, no, the main organelles for muscle energy are mitochondria. Wait, the question is about "great abundance" in leg muscles (which are active, need energy). Mitochondria are abundant in muscle cells for ATP. Lysosomes: maybe for breakdown, but maybe the intended answer is b? Wait, no, maybe I made a mistake. Wait, let's re - check:

Muscle cells (skeletal muscle) have a lot of mitochondria (for energy) and also, lysosomes are present but not as abundant as mitochondria. Wait, the options:

a) Vacuoles/vesicles: no.

b) Mitochondria (energy) and lysosomes (breakdown of damaged organelles during exercise). Maybe this is the intended answer.

c) Nucleus and cytoplasm: cytoplasm is not an organelle, nucleus is one but not abundant for function here.

d) Rough ER and ribosomes: make proteins, but muscle cells have myofibrils made of proteins, but are rough ER and ribosomes abundant? Maybe, but the main energy - producing organelle is mitochondria. So between b and d. Wait, the question is about "great abundance" in leg muscles (which are working hard, need energy). Mitochondria are abundant. Lysosomes: maybe for recycling. So the answer is b? Wait, no, maybe the correct answer is b. But I think there is a mistake. Wait, the correct organelles for muscle cells (high energy) are mitochondria and also, the sarcoplasmic reticulum (a type of ER), but among the options, b is the only one with mitochondria. So:

• Option a: Vacuoles/vesicles not key for muscle function. Eliminate.
• Option b: Mitochondria (produce ATP for muscle activity) and lysosomes (break down waste/damaged components from exercise) are abundant in active muscle cells. Correct.
• Option c: Nucleus/cytoplasm not organelles (cytoplasm is a region) or not abundant for this function. Eliminate.
• Option d: Rough ER/ribosomes make proteins, but not the most abundant for muscle energy/function. Eliminate.

Answer:

d. cell membrane

Question 2 (Organelles in Muscle Cells)